A sleeping mat is essential for a comfortable tent stay when hiking. In warm seasons, a thin, lightweight model is often sufficient, but when the cold season arrives, you'll want something with better insulation
When it comes to lightweight, highly insulating mattresses, air mattresses are the most common. However, warmer, lighter models tend to be more expensive, and there's a trade-off between insulation, lightness, and price. It's been common knowledge that if you gain one thing, you have to lose something else
One interesting new product that may overturn conventional wisdom about air mattresses the Arata ASP -R7 . I had the opportunity to try it out, so I'll give you my review.
Arata named after the two words "new" and "change," has been gaining attention since the release of its tent last year. Arata is a highly balanced mat that is on another level, combining portability, insulation, comfort, and cost-effectiveness.
table of contents
Main features of the arata ASP-R7
The arata ASP-R7 is an air mattress designed for all seasons, suitable for use in Japan's mountainous environments, including the Northern Alps in the harsh winter at altitudes of 3,000 meters. The lineup includes two types: the "Regular" rectangular mattress with ample width, and the "Mummy" lightweight mattress with trimmed-down sections, allowing you to choose the mattress that best suits your desired comfort and hiking style.
To withstand the Northern Alps' temperatures of -25°C and below, the mat is designed to be extremely lightweight and compact, while maintaining high insulation (R-value 6.7 for the Regular size and 6.6 for the Mummy size) thanks to a multi-layer structure combining TPU film and heat-reflective PET film. As a result, the Regular size weighs approximately 584g, and the Mummy size approximately 477g, making it an all-season sleeping mat
Favorite points
- High insulation properties that allow for stand-alone use during harsh winters
- Thick enough to absorb unevenness in the ground and provide a comfortable sleeping experience
- High portability for insulation and comfort
- Unprecedented cost performance
Points of concern
- Valves on the ground side make it difficult to fine-tune the air pressure later
- Durability is minimal
Main specifications and evaluation
| Item Name | arata ASP-R7 / Mummy | arata ASP-R7 / Regular |
|---|---|---|
| size | 183 x 51 x 10 cm | 183 x 56 x 8 cm |
| Storage size | φ10 x 22cm | φ10 x 25cm |
| Mat Thickness | 10cm | 10cm |
| weight | 477g | 584g |
| Surface material | 20 ripstop nylon | 20 ripstop nylon |
| Insulating material | Multi-layer structure combining TPU film and heat-reflecting PET film | Multi-layer structure combining TPU film and heat-reflecting PET film |
| R-value | 6.6 | 6.7 |
| Seasonal | 4 seasons | 4 seasons |
| accessories |
|
|
| Outdoor Gearzine Review | ||
| Comfort | ★★★★☆ | ★★★★★ |
| Thermal insulation | ★★★★★ | ★★★★★ |
| weight | ★★★★★ | ★★★★☆ |
| Storage capacity | ★★★★★ | ★★★★☆ |
| Ease of use | ★★★☆☆ | ★★★☆☆ |
| durability | ★★★☆☆ | ★★★☆☆ |
| Versatility | ★★★★☆ | ★★★★★ |
Detailed Review
For this review, we mainly used the Mummy size and conducted field tests, so we will be reviewing it based on the user experience of the Mummy size
High insulation properties that allow for stand-alone use during harsh winters
I am proud to say that I am one of the people in Japan who has had the most sleepless nights due to the cold coming from the ground, so I know more than anyone else how important a sleeping mat is
Being unable to sleep because your feet are cold can be extremely painful, and in extremely cold environments, it can be a life-or-death issue. The ASP-R7 has an R-value (measured as insulation) of 6.6 (ASTM standard F3340-22). Its design boasts an R-value that's strong enough to withstand temperatures below -25°C, making it fully capable of handling Japan's mountainous regions. According to data from the Japan Meteorological Agency, the coldest temperature ever recorded was -41°C in Asahikawa, Hokkaido, in January 1902. While the ASP-R7 alone would be inadequate in temperatures this low, its specifications make it suitable for use in weather conditions generally favorable for mountain entry, and without the arrival of a severe cold wave that would prevent anyone from even entering the mountains.
Air mattresses come in a variety of structures, including types that contain insulating material such as down or synthetic fibers, types that form layers with insulating film to suppress convection, and types that combine insulating material with a layered structure.The ASP-R7 uses a structure that combines TPU film and heat-reflecting PET film to form layers, ensuring thermal insulation.
With an R value of 6.6 the ASP-R7 actually?
Since people perceive cold differently, this is only a guideline, but in my experience, the coldest environment I have ever experienced was camping in the Southern Alps, where temperatures dropped to minus 20 degrees Celsius. The mattresses I used at the time were a combination of a closed-cell mattress and an air mattress, and the combined R-value was about 5.8, so I was able to stay warm without feeling any cold from the ground
Compared to the insulation of the ASP-R7 , there was no noticeable difference in temperature, and it felt just as highly insulating as it did then. When I actually lay down directly on the mat, I immediately began to feel a gentle warmth, and I could feel the heat-reflecting film reflecting my body heat. Compared to the mat with an R-value of 5.8, the ASP-R7, with its R-value of 6.6 on its own, allowed me to use it without worrying about the mat shifting, and without any stress. The 0.8 higher R-value in terms of insulation also gives me a sense of security.
It has high insulation, so it may be overkill in hotter weather, but you can adjust it by thinning the sleeping bag a little. In any case, this is a high-quality insulator that can be used all year round
When you place your hand on it, it gradually becomes warm
Thick enough to absorb unevenness in the ground and provide a comfortable sleeping experience
Comfortable, like bringing a bed to the field
The thicker a multi-layered air mattress is, the better its insulation, which can be considered an advantage, but personally, as the thickness increases, it can have a fluffy, squishy feel that is characteristic of air mattresses, which I dislike as someone who has always used foldable closed-cell mattresses that don't require air to be pumped in. The ASP-R7 is 10cm thick in Mummy size, and I was concerned about the impact that thickness would have on comfort, but when I actually slept on it, it didn't feel squishy at all and was perfectly comfortable.
It flattens out uneven surfaces, providing a comfortable sleep, and the surface structure reduces the fluffy feeling typical of air mattresses. It also creates space between the mattress and your body, preventing the surface from getting too stuffy. Its 10cm thickness means you won't feel any pressure on the mattress even when sleeping on your side, making it very comfortable
The 10cm thickness helps to flatten uneven ground
Although the Mummy size is slightly shaped towards the feet, the tip of the toes is large enough for your feet to rest on, so you won't feel cramped while sleeping
With highly insulating air mattresses, the insulating film inside can make a rustling noise, which is an important factor in how comfortable you sleep. the ASP-R7 before inflating it, the insulating film makes a rustling noise, but when you inflate it and sleep on it, the rustling noise is very minimal. I wouldn't say it's zero, but it's not noticeable, and I didn't notice it at all when I was inside the sleeping bag.
Air mattresses make a rustling noise every time you turn over, which can be a nuisance to your partner sleeping in the same tent, but the ASP-R7 won't be a problem.
The regular size of 56cm wide is an excellent fit
The width of the Mummy size is 51cm, the same as many air mattresses. This is just at the limit where an adult male's arms might fall when sleeping. We've narrowed the width to the bare minimum to strike a balance between lightweight and comfort. For those who want a little more space when sleeping, we recommend the Regular size, which is 5cm wider than the Mummy size and measures 56cm, which is just right. With your arms down, you can fit snugly on the mattress without feeling cramped. The unshaped foot and head areas make it feel like you've brought a bed to the field
The 5cm wider seat makes it less cramped
A pump sack that can be inflated in three tries
The pump sack that comes with the ASP-R7 the ASP-R7 , which can be inflated in just three tries, was stress-free.
Made of nylon and slippery
The surface fabric of air mattresses is made of nylon or polyester. Nylon has a higher strength-to-fiber ratio and is lightweight, so nylon mattresses are becoming more common in today's world where lightweighting is becoming more and more important. The ASP-R7 is also made of nylon.
Nylon has the advantage of being lightweight, but it also has the disadvantage of being slippery due to its low coefficient of friction, making it easy for players to slip off the mat on sloped fields. ASP-R7 also tends to be slippery on sloped surfaces due to the characteristics of the fabric, so some kind of countermeasure will be necessary. (We will introduce recommended countermeasures later in this article.)
The valve is on the back (ground side), so it's difficult to adjust the firmness
One thing that bothered me was that the air valve was on the back (the side facing the ground). While having the valve on the ground side is beneficial in that it doesn't bother you while you're sleeping, it also means that you have to turn the mattress upside down when inflating it, and adjusting the amount of air after inflating it is also a bit of a pain
High portability for insulation and comfort
Comparison with a 500ml plastic bottle. The left is Mummy size, the right is Regular size
Equipment for the harsh winter tends to be heavy even in the extreme cold. When planning a mountain hike in the extreme cold, it would be foolish to try to lighten your cold weather gear. As a result, there are few ways to lighten it, and carrying heavy equipment is a fate, but the ASP-R7 .
Despite providing insulation that can withstand temperatures as low as -30°C and providing a comfortable sleeping experience, it weighs just 477g (Mummy size), making it an attractive option for those looking to save weight when hiking in snowy mountains. Even with the pump sack, storage bag, and repair patch included, it weighs just 560g, making it a lightweight, compact, and highly portable mat considering its insulating properties
Weight includes main unit, storage bag, pump sack, and repair kit
The balance between lightweight and comfort is often a trade-off, and it's difficult to achieve both. However, for those who want to save weight without sacrificing comfort, the Regular size is a good choice, weighing just 584g while still maintaining a comfortable sleeping experience (the total weight of the Regular size, including accessories, is 672g)
Puncture protection and thermal insulation boost! The world's lightest closed-cell mat weighing just 42g
One problem that all air mattresses face is the risk of punctures. In a world where temperatures are minus 30 degrees Celsius, punctures are one of the problems you want to avoid at all costs. Some people even choose not to use air mattresses because they don't want to take the risk of a puncture
An effective way to prevent punctures when using an air mattress is to use it in combination with a closed-cell mat. Placing a mat between the ground and the air mattress is an effective way to prevent punctures caused by damage to the air mattress, and I personally use it in conjunction with a closed-cell mat when I take my air mattress out. However, carrying two mats does increase the weight of my equipment. I had accepted this as an unavoidable measure to reduce the risk of punctures, but Arata also has a closed-cell mat in their lineup, the ASP-03 . It is 180cm long and covers the entire body, yet weighs just 42g. This makes it possibly the lightest closed-cell mat in the world that covers the entire body.
Ultra-lightweight mat weighing just 42g
Adding 42g to an air mattress can reduce the risk of punctures, so it's probably a good thing. The ASP-03 is 0.4mm thick and has an R-value of 0.45, which provides a slight boost in insulation. Its surface is designed with a high coefficient of friction, even among polyethylene mattresses. the ASP-03 and an air mattress also provides anti-slip properties, providing protection, warmth, and anti-slip performance in one.
If you put it underneath, it will protect your air mattress
Cost performance that can be called another dimension
the ASP-R7 insulation that can withstand temperatures as low as -30°C, providing a comfortable sleeping experience, but despite its high specifications, it also offers incredible cost performance.
While prices are rising and the prices of all brands of mats are increasing, the ASP-R7 is priced at 20,000 yen for both the Mummy and Regular sizes. This aggressive pricing makes us a little worried about the manufacturers, but it is true that it is easy on the user's wallet. Let's be grateful for the benefits.
Since purchasing all the necessary equipment for winter mountain climbing requires a huge budget, the cost-effective ASP-R7 is also recommended for hikers who want to take on the challenge of mountain climbing in temperatures as low as -30°C.
Summary: An all-season air mattress that offers insulation, comfort, portability, and cost-effectiveness
We introduced Arata's air mattress ASP-R7
In a world as cold as -30°C, the peace of mind of not feeling cold when sleeping is truly a godsend. Carry a comfortable bed with you into the field that will keep you warm rather than cold when you lie down, and recover your energy for the day ahead, ready for the next day!
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Yosuke
A person who travels around with just one backpack, with the motto of "as light as possible" without causing inconvenience
From spring to autumn, I go fishing in mountain streams in pursuit of char deep in the mountains. I hike the mountains in search of spectacular views that cannot be seen from the ground. I camp to relax by a bonfire. I snowboard to experience the feeling of floating in the silvery white mountains
A freelance writer with over 20 years of outdoor experience who enjoys the outdoors in his own way all year round. Based on his experience writing articles for over a dozen outdoor web publications, he will share his own experiences and the best tools he has used
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