Best Hot Tubs

The Spruce / Sabrina Jiang

Hot tubs offer year-round, spa-like relaxation right in the comfort of your home. As tempting as it may be to start clearing out your backyard in anticipation of a new water feature, do keep in mind that hot tub ownership is a responsibility.

Rick Hagen, who handles National Sales for Outdoor Living Products at Pool Corp and is part of the Pool and Hot Tub Alliance, emphasizes that safety and sanitation are the top priorities when it comes to hot tub maintenance and ownership. “Whether you get an inflatable or a standard hot tub, you need to make sure that you practice good safety,” he says. Not only does this include general water and pool safety (“If you’re not using it, make sure you’ve got it covered,” Hagen says), but it also ensures that it’s chemically balanced, too. Thankfully, manufacturers will give clear instructions for how to maintain their products, so you can focus on safely enjoying them as much as possible.

If you’re considering one for your backyard or patio, know that not all hot tubs are created equal. We researched dozens of models—and even tested a few popular hot tubs in our own backyards—evaluating them based on design, size, maintenance requirements, and standout features.

Best Overall

Aquarest Spas Select 150 4-Person 12-Jet Rectangular Plug-and-Play Hot Tub

Wayfair Aquarest Spas Select 150 4-Person 12-Jet Rectangular Plug-and-Play Hot Tub


  • Plug and play design

  • Easy to maintain water levels

  • Backlit waterfall

  • Uses standard volt plug

  • Not as large as other models

  • Steps are added expense

During testing, we found very little to dislike about the Aquarest 150 Select. The entire setup process, from delivery to filling, was a complete breeze. We especially appreciated the thorough communication leading up to and during the delivery. There wasn’t much to “set up” in this hot tub. We simply removed all of the packagings and plugged it into a standard 120-volt outdoor plug—a super convenient feature compared to others that require high-voltage plugs.

This model is one of the few hot tubs that appropriately can be called a Jacuzzi since it’s powered by a 1.5-hp Jacuzzi brand pump. It’s also full of standout features: 12 stainless steel hydrotherapy jets, a backlit waterfall with nine color settings, four cup holders, a locking safety cover, and a patented water filtration system. While the online listing says this hot tub can fit up to four adults, we found that two adults and two children were cozy, so four adults might be crowded. At most, we think two adults could comfortably stretch out and feel comfortable. The seats in this hot tub were also surprisingly nice and not overly slippery compared to others we had used.

You can purchase a storage step that hooks onto the hot tub body, but we did not think this was necessary as it’s very easy to climb in and out of this model. We found children could also easily navigate it as well. We recommend purchasing the suggested care kit as well as some water testing strips to ensure your water levels are clean. The chlorination process and maintenance involved weren’t too overwhelming for us. We simply checked the water on a weekly basis and added any necessary chemicals. We also rinsed the filter every week or more often, depending on how often we used it. All in all, this hot tub is a great smaller model at a reasonable price. Plus, it’s loaded with fun features.

Price at time of publish: $3,000

Dimensions: 59 x 69.5 x 30.5 inches | Shape: Rectangular | Water Capacity: 156 gallons | Jets: 12

  • The Spruce / Jodi Espinosa

  • The Spruce / Jodi Espinosa

  • The Spruce / Jodi Espinosa

  • The Spruce / Jodi Espinosa

Best Inflatable

Intex PureSpa Plus 6-Person Portable Inflatable Hot Tub

Intex PureSpa Plus Portable Inflatable Hot Tub Spa


  • Great for beginner hot tub users

  • Air-filled headrests

  • Built-in hard water treatment system

  • Inflates in 5 minutes

  • Extensive setup time

  • Not equipped with many features

The Intex PureSpa Plus is a generously sized inflatable hot tub with 170 bubble jets and a built-in hard water treatment system. While this hot tub technically took us almost an hour to set up before filling it with water, that was mostly due to the confusing instructions. We realized that the instructions were likely written to apply to multiple models from Intex, so not everything we read was meant for the PureSpa Plus. However, the hot tub itself inflated in just 5 minutes. It took an hour and 45 minutes for it to be filled to the max water line. Consider this model practice in delayed gratification because it takes 32 hours to heat up—making us realize that there’s only so much spontaneity involved with this model if you hope to store it and pull it out when desired.

We appreciated that the hot tub accessories in this kit: An insulated cover, LED light, two filter cartridges, two inflatable headrests, a thermal ground cloth, an inflation hose, a carry bag, and a floating chlorine dispenser are all included. Two non-slip seats are also shipped with this hot tub, but we will say that we found the hot tub surprisingly comfortable even without the seats. It’s also pretty sturdy when filled completely, so you can gently rest on the sides if you need a moment to cool off from the hot water. We didn’t have an opportunity to test the LED lights at night due to some neighborhood regulations, but we think they’d be a fun feature, especially if you have kids that want to enjoy it.

Like most inflatable models, the Intex PureSpa Plus is slightly more fragile than its cabinet-based counterparts, and it’s also not recommended for use in freezing climates. And, it’s worth noting that we evaluated the six-person model but found that you’d be more comfortable seating at most four people. As long as you empty this model two to three times a month (if using it regularly) and maintain proper chlorine levels, we think it’s a great alternative to a permanent fixture.

Price at time of publish: $864

Dimensions: 85 x 85 x 25 inches | Shape: Round | Water Capacity: 290 gallons | Jets: 170

  • The Spruce / Kimberly Souza

  • The Spruce / Kimberly Souza

  • The Spruce / Kimberly Souza

  • The Spruce / Kimberly Souza

  • The Spruce / Kimberly Souza

Best Budget

Bestway SaluSpa Miami 4-Person Inflatable Hot Tub

Amazon Bestway SaluSpa Miami Inflatable Hot Tub, 4-Person AirJet Spa


  • Fast heat up time

  • Easy to reach control panel

  • Built-in cup holders

  • Instructions not included in box

  • No seats or headrests

A budget doesn’t have to limit your relaxation! This Bestway inflatable hot tub impressed us with its easy-to-operate control panel and fast heat-up time. It may not be the largest hot tub on the market, but for under $600, we were more than satisfied with its performance. Our main frustration with this hot tub is that it did not come with any assembly or inflation instructions. We had to look them up online, but once we found the appropriate instructions, we found the process simple. It took about two hours to fill this hot tub with water and only 12 hours to reach 100 degrees.

While there are no seats or headrests provided with this model, we found it comfortable enough to sit on the tub floor. As we discovered with our other tested models—our Best Overall and Best Inflatable—this hot tub likely would be crowded with the suggested max of four people. We think three adults would even be a little crowded but manageable. Thanks to this hot tub’s low profile, it’s relatively easy to climb out of. We also appreciated the built-in cup holder on this model. Our only other note of caution is that the jets for this hot tub are located at the bottom rather than around mid-back. We didn’t find this to be too disappointing, just an interesting design choice.

Price at time of publish: $530

Dimensions: 71 x 71 x 26 inches | Shape: Round | Water Capacity: 177 gallons | Jets: 120

  • The Spruce / Andrea Tenborg

  • The Spruce / Andrea Tenborg

Best Splurge

Canadian Spa Company Okanagan 10-Jet Plug-and-Play Hot Tub

Canadian Spa Company Okanagan 10-Jet Plug-and-Play Hot Tub


  • Rotating hydrotherapy jets

  • Color-changing LED

  • Microban filtration and ozone generator

  • Only 10 jets

If you’re open to spending a bit more on a high-end hot tub, the Okanagan is a stellar choice. This circular design comfortably seats up to four adults, while 10 stainless steel rotating hydrotherapy jets offer a relaxing, spa-like massage. You can adjust the jets in many different configurations and directions to vary the type of massage.

With a 63-inch diameter, this hot tub shouldn’t take up a huge amount of space on your deck or patio. We also like that this is a deeper spa than many we’ve seen: Its 29-inch depth may allow you to fully submerge your shoulders.

The Okanagan leans on an ozone generator and Microban filtration to keep your water crystal-clear and free of bacteria with minimal chemicals. It also has a color-changing LED light, allowing you to customize the ambiance. You also get a hard-top cover. And thanks to the plug-and-play design, you don’t have to hire a professional for installation.

Price at time of publish: $5,765

Dimensions: 63 x 63 x 29 inches | Shape: Round | Water Capacity: 185 gallons | Jets: 10

Best Portable

Coleman Saluspa Miami AirJet 4-Person Inflatable Hot Tub Spa with Pump

Coleman Saluspa Miami AirJet 4-Person Inflatable Hot Tub Spa with Pump


  • Costs less than many alternatives

  • Pump and filter included

  • User-friendly and easy to move

  • No steps

  • Not ideal for cold climates

Interested in something more portable? Consider an inflatable model, like the Coleman SaluSpa Miami. This air-filled hot tub is made of heavy-duty plastic and comes with its own pump and filter. It inflates in minutes, according to the manufacturer. And an included chemical dispenser provides a stable level of chlorine.

The plug-and-play design seats two to four people around its three-ply PVC walls. It’s easy to move around in, but you may not have to since 60 jets spread the waves around throughout. You can control the temperature and jets with a convenient digital control panel.

We like that the hot tub includes a cover to keep the water warm when you’re not using it. But we should note the Miami is intended for use in climates above 39 degrees Fahrenheit, so if it’s freezing outside, hold off (although, there are models with a Freeze Shield™ technology if usage during cold temperatures is a top priority). Also, we would have liked to see a longer warranty than for the pool liner (3 months), spa cover (6 months), and pump and heater (1 year). The manufacturer offers an extended warranty, up to 18 months, for a cost.

Price at time of publish: $970

Dimensions: 71 x 26 inches | Shape: Round | Water Capacity: 192 gallons | Jets: 60

Best Extra-Large

Lifesmart Coronado 7-Person 65-Jet Spa with Turbo Blaster

 Lifesmart Spa with 14-Jet Nozzle Turbo Blaster

The Home Depot

  • Seven-person capacity

  • Energy-efficient heating

  • Color-changing LED

  • Other alternatives cost less

  • Steps sold separately

For something larger, consider the Lifesmart Coronado. While the price is steep, we think it’s still a reasonable value for a high-quality hot tub of this size. This seven-person tub has 65 jets, including 14 with turbo-blaster nozzles and four foot massagers. The energy-efficient design features full-foam insulation and a thermal locking cover that keeps the heat in.

The Coronado also has a waterfall, a multi-colored underwater LED, a built-in filter, and an ozonator that cleans the water with minimal chlorine. If you want a large hot tub with all the bells and whistles, it’s definitely worthy of your consideration.

Price at time of publish: $4,200

Dimensions: 81 x 81 x 34 inches | Shape: Square | Water Capacity: 285 gallons | Jets: 65

Best Small

Aquarest Spas 300 Select 2-Person 20-Jet Oval Plug-and-Play Hot Tub

Aquarest Spas 300 Select 2-Person 20-Jet Oval Plug-and-Play Hot Tub


  • Cup holders

  • Backlit LED waterfall

  • Energy-efficient heating

  • No steps

Aquarest Spas makes the best hot tubs for two people. This compact hot tub has deep, bucket-style seats with 20 strategically placed stainless steel massaging jets. Two cup holders keep your drink of choice within reach, and a digital control panel allows you to change the intensity and direction of the jets. The manufacturer claims the lumbar-support design aids comfort, too.

The 300 Select also flaunts a backlit LED waterfall with nine color modes. You also get energy-efficient heating with foam insulation, a patented filtration system, and a locking safety cover. In the end, the only thing this tub doesn’t have is steps.

Price at time of publish: $3,500

Dimensions: 80 x 68 x 31 inches | Shape: Triangle/oblong | Water Capacity: 160 gallons | Jets: 20

Best Oval

Lifesmart Spas Celestial 4-Person 13-Jet Oval Plug-and-Play Hot Tub

Lifesmart Spas Celestial 4-Person 13-Jet Oval Plug-and-Play Hot Tub


  • Unique shape

  • Bucket and bench seats

  • Energy-efficient heating

  • Only 13 jets

  • No steps

Interested in something other than a square or circle? Check out the Lifesmart Celestial Hot Tub. Fit for four adults, this oval-shaped spa, with 13 jets, has two bucket seats on one side and a longer bench-style seat on the other. Three cup holders keep beverages at hand, and you can control the temperature, jets, lights, and more with the control panel, located on the rim.

Like all Lifesmart models, this one is energy-efficient, with foam insulation and a thermal locking cover. While it doesn’t have stairs, you can purchase those as an add-on, crafted to fit the contours of most hot tubs made by the manufacturer. The Celestial does come with its own filtration system and a thermal friction pump, too.

Price at time of publish: $3,999

Dimensions: 77 x 66 x 29 inches | Shape: Oval | Water Capacity: 220 gallons | Jets: 13

Best Round

Ohana Spas Balance 7-Person 25-Jet Round Hot Tub

Ohana Spas Balance 7-Person 25-Jet Round Hot Tub


  • Underwater LED light

  • Energy-efficient heating

  • User-friendly control panel

  • Alternatives can cost less

  • No steps

At nearly 7 feet in diameter, the circular Balance Hot Tub from Ohana Spas is bigger than it looks. It fits up to seven adults in its comfortably contoured seats. The plug-and-play design has 25 massaging jets and an underwater ambiance-enhancing light, and the user-friendly control panel makes it easy to turn on the jets, adjust the LEDs, and change the water temperature. You can opt for three programmable modes to control energy use. We note that this is either a plug-and-play into a standard 110-volt electrical outlet, or a 240-volt circuit.

This UL-listed and CSA-certified hot tub comes with a filter and an insulated locking cover. But, like so many products we evaluated, it doesn’t include steps, which have to be bought separately.

Price at time of publish: $5,700

Dimensions: 80.5 x 34.5 inches | Shape: Round | Water Capacity: 270 gallons | Jets: 25

Best Wood-Fired

Alfi Brand 4-Person Round Wood Fired Hot Tub

Alfi Brand 4-Person Round Wood Fired Hot Tub


  • Unique design

  • Portable

  • No electricity required

  • Expensive

  • Limited features

Have you considered a wood-fired model? Alfi Brand makes the best one on the market. This unique hot tub is crafted from an antimicrobial material that stands up to ultraviolet-ray damage and freezing temps, according to the manufacturer (in moderate temperatures, it takes about three hours to heat 130 to 220 gallons of water to 100 degrees Fahrenheit, for context).

Yes, this hot tub’s concave shape does remind us a little of a witch’s cauldron, especially since it heats from a wood fire in the pit. The advanced coiling system heats up with burning firewood (aka convection)—no power cord or outlet needed. But you’re protected from the flames by extended pipes and a stainless steel windscreen panel. (Yes, you can cook over the flames while waiting for the water to heat.)

Gratefully, the honey-orange color and its fiberglass-reinforced acrylic makeup remove all comparisons to anything Hansel and Gretel-ish. This four-person hot tub can be brought on the go or moved around your outdoor living space as needed. It’s undoubtedly expensive, but it might be worth a splurge if it’s within your budget.

Price at time of publish: $6,950

Dimensions: 63 x 63 x 32.33 inches | Shape: Round | Water Capacity: 220 gallons | Jets: 0

Our Best Overall pick, the Aquarest Spas 4 – Person 12 – Jet Rectangular Hot Tub, is just the right size for anyone who’s looking to test the waters of a hard-shell hot tub without committing to a super large unit. We loved the cupholders, comfortable seats, backlit waterfall, and powerful jets included in this model. Alternatively, you can save money with our Best Budget pick, the Bestway SaluSpa Miami Inflatable Hot Tub, which comfortably seats three adults and is easy to inflate and fill with water.

How We Tested the Hot Tubs

Due to their size and the restrictions that come with them, we could only test three hot tubs during our initial at-home testing. However, we took this opportunity to learn all about the setup process of each type—hard shell versus inflatable—and the required maintenance. During the initial phase of testing, we noted how smooth the delivery process was and where the delivery personnel dropped off the package in relation to our desired placement. Then we timed how long the setup process took for each hot tub. This included unpackaging and assembling any parts. For the two inflatable models we tested, the inflation process counted toward this time. We then separately timed how long it took to fill each hot tub and even made note of how long it took for the water to warm to 104 degrees Fahrenheit.

We then used the hot tubs regularly for two weeks and, during this time, took note of the design and features. We considered how easy it was to adjust the temperature and other settings, and we noted any add-ons like waterfalls, LED lights, and extra jets. Maintenance is an essential part of hot tub care, and we followed any provided manufacturer instructions for emptying the water, changing or refreshing chemicals, and rinsing the filters. At the end of the two-week testing period, we assessed the value of each model. This involved considering whether we’d buy the model independently or if we’d change anything about the design and functionality.

back of person's head who is sitting in Intex PureSpa Plus 6-Person Portable Inflatable Hot Tub

The Spruce / Kimberly Souza

What to Look For in a Hot Tub


The best type of hot tub depends on your budget, preferences, and available space. Above-ground plug-and-play models, like our Best Overall pick, the Aquarest Spas 4 – Person 12 – Jet Rectangular Hot Tub, are durable and long-lasting, with molded exteriors and sturdy locking covers. If you have room for a hot tub but don’t want to dig into your yard, this is a great option.

Inflatable hot tubs, like our Best Inflatable pick, the Intex PureSpa Plus, are the most affordable, though they’re also more prone to wear and tear. Like their rigid-shell counterparts, air-filled models typically plug into standard electrical outlets, and they can be moved around or even taken on the go (when they’re drained, deflated, and dry).


Hot tubs come in various shapes and sizes. Capacities range from one- or two-person models, like our Best Small pick, the Aquarest Spas 300 Select, to seven or more people, like our Best Extra-Large pick, the Lifesmart Coronado. Before buying a hot tub, carefully measure your space and check the overall assembled dimensions to ensure it’ll fit.


Hot tubs are often made of polyethylene, an exceptionally durable and weather-resistant thermoplastic. They can also be constructed from high-strength fiberglass or UV- and freeze-resistant acrylic, as with our Best Wood-Fired pick, the Alfi Brand Wood Fired Hot Tub. Inflatable models, like our Best Budget pick, the Bestway SaluSpa Miami Inflatable Hot Tub, are usually made of puncture-resistant vinyl.

Extra Features

To make the most of your lounging hot tub experience, consider investing in a model that has the features you want. This can include jets, multi-colored lights, and even built-in speakers. Lounge seating is another popular feature, although it does often make the hot tub larger. Some manufacturers even offer customized hot tubs that you can design yourself.

When looking into extra features, consider those that increase the life span of your hot tub. Balancing chemicals, a hot tub cover, or routine maintenance can all come as part of a hot tub package or purchase. While an extra cost up front, getting these extras may save you money in the long run.


Also, consider the maintenance requirements of a hot tub before buying one. Many come with built-in filtration systems and ozone generators (aka ozonators). This helps keep the water clean and free of bacteria while using lower amounts of chlorine and other chemicals.

Still, you need to change the filter cartridge regularly and drain and refill the water periodically. Also, make sure your hot tub is always covered when it’s not in use. Following hot tub best practices will ensure you get the most out of your purchase.

  • How do you set up a hot tub?

    Setting up your hot tub for the first time isn’t as daunting as it may sound. Assuming you have the proper electrical outlet available (either 110V or 240V) and a level surface (preferably concrete or a specially designed hot tub pad), the process is as simple as having the tub delivered to your yard, freeing it from the packaging, and filling it with water.

    In the case of an inflatable hot tub, take extra steps to ensure that there are no objects on the ground that could puncture the lining. Remove any rocks, sticks, and debris before inflating the hot tub. A ground cover is often included with inflatable hot tubs and serves as an additional layer of insulation and protection, but it is no substitute for a careful site evaluation before setup.

    Before you break out the hose, turn off the power to the circuit in your breaker box. Clean the hot tub using a mild, nonabrasive formula. Verify that all jets and knobs are in place. Open gate valves and close drain valves, then install the skimmer and filter. Next, use a garden hose to fill the tub with water.

    Restore power to the breaker. Power on the hot tub and prime the pump (usually, there will be an option for this on the hot tub’s control panel). Finally, set the hot tub to your desired temperature and begin heating the water inside before dispensing chemicals into the water for proper hygiene and water maintenance.

  • How often should you clean a hot tub?

    It’s usually recommended to drain and clean your hot tub every three to four months; however, you should adjust based on your frequency of use. A deep clean of the hot tub involves flushing the lines; draining the water; and scrubbing the tub shell with hot tub cleaner, white vinegar, a diluted bleach solution, or an all-purpose non-abrasive household cleaner. (Consult manufacturer guidelines for specific cleaning product recommendations.) Thoroughly wipe the shell, seats, and jets to remove any grime or bacteria. Be sure to rinse well and dry the tub with a towel to avoid chemical contamination. Refill the tub with water. You should also remove the filters occasionally and spray them with a garden hose or hot tub cleaner. Rinse well before reinstalling. This should be done more frequently—even up to once per week for frequent hot tub users.

  • What chemicals do you need for a hot tub?

    Hot tubs need regular cleaning to maintain safe, clean water and proper functioning of the system. Test your water frequently and keep these hot tub chemicals on hand:

    • PH adjusters: Muriatic acid or sodium bisulfate are used as pH decreasers. Muriatic acid (or a replacement product) also can lower alkalinity. Sodium bisulfate can raise alkalinity.
    • Alkalinity increaser: Alkalinity and pH are closely related, so adjusting the pH levels of your hot tub can also impact alkalinity. If you need to raise the alkalinity of your hot tub, use an alkalinity increaser.
    • Shocking agent: Use either chlorine or a nonchlorine treatment that breaks down organic compounds in the water and also converts chloramines back into the active form of chlorine.
    • Sanitizer: The most popular options include chlorine and bromine. Bromine is sometimes recommended for people with more sensitive skin. Other sanitizing options for your hot tub include biguanide (a non-chlorine and nonbromine chemical sanitizer), a salt system, or an ozone generator.
    • Calcium hardness increaser or decreaser: Depending on your water hardness, you might need an additive to increase or decrease the amount of calcium in your hot tub water. This gives you clearer water while prolonging the life of mechanical components.
    • Enzymes: While not an absolutely essential chemical for your hot tub, enzymes help to slow the buildup of hot tub scum.
    • Filter cleaner: This is a special cleaning formula that helps to purge debris and buildup from the filter, extending its life. Use it when you do a deep clean of your hot tub, every three to four months.
  • What is the life span of a hot tub?

    You can generally expect a hot tub to last 10 to 15 years, but the life span really depends on the material, build quality, environmental conditions, and how well it’s maintained. Also, certain parts and components can be repaired or replaced over the years before it’s time to replace the entire thing.

    The life span of inflatable tubs is much shorter. If you’re lucky enough to avoid a non-repairable hole, you can expect an air-filled hot tub to hold up for three to five years.

  • How much does it cost to install a hot tub?

    Many modern hot tubs are designed for plug-and-play, meaning professional installation usually isn’t required. If you need a pro, you can spend $100 to $500, depending on the needs. If you’re building your hot tub into a pool or designing a below-ground spa, the project will likely run you several thousand dollars.

  • Do hot tubs draw a lot of electricity?

    It varies among models, but residential hot tubs typically draw 1,500 to 6,000 watts of energy. In terms of what this looks like on your power bill, a plugged-in hot tub costs you anywhere from 50 cents to $2 a day.

  • Is a hot tub a Jacuzzi?

    Much as Kleenex is a brand name for tissues and Xerox a brand name for office copiers, Jacuzzi is in fact a trademarked brand name for jetted tubs and other spa equipment. In 1956, the Jacuzzi brothers created the original hydrotherapy bath with the invention of an underwater pump that arthritis patients could use to relieve pain. A decade later, Jacuzzi created the world’s first integrated jet whirlpool bath. Another decade later, the company invented large, indoor, jetted tubs that could accommodate multiple people.

feet next to Intex PureSpa Plus 6-Person Portable Inflatable Hot Tub

The Spruce / Kimberly Souza

Why Trust The Spruce?

This article was written by Theresa Holland, a commerce writer and product reviewer specializing in home design, lifestyle, and outdoor living. You can read more of Theresa’s stories on MyDomaine, People, and Travel + Leisure. Emma Phelps, an associate commerce editor for The Spruce, updated this roundup to include insights from our recent round of testing three hot tub models. During this at-home testing period, our team evaluated the setup, design, maintenance, and features of each hot tub. Phelps not only assessed our notes on each hot tub but also compared their performance to our previously researched selections.

What Is The Spruce Approved?

Here at The Spruce, we want to ensure we fully stand behind every product we recommend and that when we say something is the best, we mean it. You might have noticed The Spruce Approved badge next to the products on this list. Every product with this badge has been rigorously tested in person and carefully selected by our expert team of lab testers and editors. In most cases, we buy all these products ourselves, though occasionally, we get samples provided to us directly by companies. No matter how we procure products, they all go through the same tests and must meet the same strict criteria to make the best-of cut.

You are watching: The 10 Best Hot Tubs of 2023, Tested and Reviewed. Info created by Bút Chì Xanh selection and synthesis along with other related topics.