Klymit Inertia X Frame Regular Mat

ASTM R-Value: Not Quoted / Dimensions: 183 x 46 x 3.8cm / Packed Size: 8 x 15cm
Weighs 258g (excluding bag)
Code: OC3163
  • £69.99
  • (FREE Delivery on orders over £15)
Item out of Stock | Usually dispatched within 24 hours

UOG TOP PICK - Klymit's Inertia X Frame Sleeping Mat - Lowest weight and packsize for any mat - We've singled out Klymit's Inertia X Frame Sleeping Mat as one of our top recommendations because they are the lightest of any type of sleeping mat with the smallest packsize, though there's a small compromise on comfort.

Klymit says:

A radically different approach to sleeping comfortably on air. There’s nothing like the Inertia X Frame™ - it provides support at key pressure points while eliminating every ounce of unnecessary material. It works especially well inside a sleeping bag where the bag’s loft fills the empty spaces in the pad. The X Frame™ also features a customizable pressure valve with hand-pump for precise comfort.

Comfort wise this pad sits somewhere between a self inflating mat and a full airbed so its not as warm or as comfortable as the insulated airbeds that we sell but its still pretty comfortable especially when compared to self inflating mats and  (God forbid) closed cell foam - and given its pack size and weight I find myself reaching for it everytime if I`m going ultralight.  

It offers no insulation itself but does allow your sleeping bag to loft into the pockets to keep you warm - really nice innovation.

- Reviewed by Ultralight Outdoor Gear

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Help and advice:

UOG TOP PICK - Klymit's Inertia X Frame Sleeping Mat - Lowest weight and packsize for any mat - We've singled out Klymit's Inertia X Frame Sleeping Mat as one of our top recommendations because they are the lightest of any type of sleeping mat with the smallest packsize, though there's a small compromise on comfort.

  • Minimalist Design: Advanced patterning removes all extraneous material to creates an ultralight, minimalist design that delivers comfort and support for only 8.5 oz. and packs to 3” x 6”.
  • Body Mapping: Advanced patterning places chambers only where padding is needed and eliminates them where they are not, allowing us to shed significant weight without sacrificing comfort.
  • Loft Pockets: Empty spaces between the chambers serve as expansion zones that allow your sleeping bag to fully loft beneath you, maximizing its thermal performance.
  • The Right Size: At 78” long, the streamlined size is tapered to fit the body and allows the pad to be used inside or outside of your sleeping bag.
  • Inflation and Deflation: Pad rapidly inflates in as few as 5-7 breaths, and a hand pump is included for more rapid inflation and the ability to reach a higher PSI. The valve’s intelligent design allows for micro adjustments to fine tune pressure and comfort.
  • Patch Kit included for emergency repairs
  • Weight: 258g (excludes storage bag + pump)
  • Pump weighs: 40g
  • Dimensions: 72" x 18" x 1.5" / 182.9 cm x 45.7 cm x 3.8 cm
  • ASTM R-Value: Not quoted
  • Inflation: 3-5 Breaths
  • Packed Size: 3" x 6" / 7.62 cm x 15.2 cm
  • Fabric: 30D Top / 75D Bottom Polyester
  • Warranty: Klymit Lifetime Warranty

ASTM R-Value:

From 2020, there is a new industry standard for measuring the R-value (level of insulation) of sleeping mats – ASTM F3340-18. This new standard is the sleeping mat equivalent to the EN rating for sleeping bags.

You can now directly compare the R-value of mats rated using the ASTM F3340-18 with confidence that is a fair and accurate comparison between mats. In simple terms, the higher the R-value, the warmer the mat.

In general terms, an R-value below 2.0 is for summer use, 2.0 to 4.0 is for cooler 3 season use and 4.0+ is for winter temperatures. This will be also be dependent on your sleeping bag, how cold you sleep etc. Please contact our customer service team if you need advice on choosing the right mat for your activity.

Showing our 2 Klymit Inertia X Frame Regular Mat reviews with an average rating of Excellent. Would you like to write a review?
Review Summary - 5 out of 5 based on 2 ratings.
November 12, 2020 | Duncan
Technology Keeps Improving

I have been hiking for approximately 30 years and owned various sleeping mats. For me this is the best yet and represents how technology has transformed wild camping over the years. Overall pros: I found this to be comfortable to sleep on and very lightweight. Overall cons: You have to position yourself a little carefully to avoid the gaps but I found this easy to do. Also, depending on the distance between your feet, hips and shoulders the more padded areas may not align well for you. Pros more detail: (1) It is not slippy, so the outer layer does not slide over my tent as much as many other mats. (2) It is lightweight obviously. (3) I found the inflatable elements to be thick enough that I did not press through into the ground and did not notice smaller bumps. (4) I was able to sleep on my back and side. (5) I am 5 foot 8 inches tall and I found the foot, hip and shoulder padding zones to be a good distance apart for me. I had my head approximately 3 inches from the top of the mat. (6) When I was side sleeping I was resting almost completely on the thinner sections of the mat and still comfortable. (7) The construction seems very strong and sturdy. Cons more detail: (1) The cold does seep through the gaps in the mat slightly. However, I made use of miscellaneous items (such as my sitting pad, waterproofs and stuffsacks) one day when the ground was very cold and this really helped. For me I think it works as a 3 season mat extending to occasional colder nights as well. Would I use it as a 4 season mat if I added a couple of extra bits of foam mat to fill the gaps? I'm not sure as I do not generally sleep out in snow and so have not optimised my kit and skills to these conditions. (2) Clearly depending on your body size the more padded areas could be in the wrong spots. (3) I think if you are fairly heavy then you could fall between the gaps in the mat. I am now going to rely on this as my only sleeping mat and improvise on very cold (approaching freezing) nights to stay warm. I immediately threw away the carry bag and I simply place it (folded fairly neatly with the air pressed out and the valve open) into my sleeping bag stuffsack before then putting my sleeping bag in afterwards.

Ultralight Outdoor Gear Limited
June 25, 2018 | Packs
Very comfortable

I found this to be the most comfortable mat I've used, even more than non-lightweight varieties. I am slight (~9st) and I could even lie on my side without discomfort. You don't have that floating feeling. Slept great on a 3 day trip and no aches or pains in the morning.

Ultralight Outdoor Gear Limited