THE FIRST TIME I SAW the Klymit Inertia X Frame ultralight sleeping pad, I was blown away by the innovation and promise: Instead of a rectangle, the Inertia X Frame is a grid of inflatable tubes — with a dozen large holes in the frame. The idea is that you don’t actually need complete and total pad coverage underneath every part of your body if all the core spots are supported by the X Frame’s grid of inflatable tubes.
Wild, I know.
Of course, the grid also means less material, and less material means less weight. Is the Intertia X Frame light? Hell yeah: 9.1 ounces. That’s it.
I think I’ve held turkey feathers that weighed more than the Inertia X Frame.
How the Inertia X Frame Works
Designed by Klymit’s body mapping research, the X Frame is supposed to give you support under key pressure zones — head, shoulders, hips, legs, and feet. Does it work?
Surprisingly well. I’m a relatively big guy, about 6’3″ and 220 pounds with wide shoulders. When I unrolled the X Frame, which came packed in a small carrying bag about the size of a Diet Coke can, it took just a few puffs of air to inflate it.
It was insanely light, 72 inches long and a bit narrow. Dubious, I tried it. I could feel the tubes running beneath my body, but I had to pay attention — had I not seen what I was laying down upon, I might have simply thought it was a standard cushy air mattress.
You don’t feel the holes.
Of course, that’s just on your back. Once you start rolling around, back-to-side, side-to-stomach, you become more aware of the support system. I expected to adjust my position to match the tubes, but in reality, I didn’t have to pay that much attention to where my knees or feet were.
Loft Pockets?
Klymit touts its “Loft Pocket” technology, which means that your sleeping bag can fluff up into the holes in the X Frame, which gives you better insulating and warmth capabilities from your bag. I used the X Frame with a mid-level synthetic bag and I didn’t get much loft out of it. I can imagine a better response from a nice down bag, but I didn’t bother to find out. Cushion is what I cared about most — but any loft is better than no loft when it comes to insulating properties.
The X Frame comes with a small hand pump, which you can use to add a couple extra pounds of pressure to the pad if you want a stiffer feel. (I was happy with what my own lungs produced.)
The Intertia X Frame isn’t all sunshine and light, though — it has two cons.
As you might expect with a blow-up mattress, Klymit includes a patch kit. Overall, the build quality is excellent, but like any inflatable, thorns will be your biggest enemy. If you travel into truly pokey parts of the world, it’s hard to recommend any full inflatable. A closed cell foam mattress like the Therm-a-Rest Z-Lite SOL is dirt-simple smarter — but heavier and much bulkier.
The last “con” depends somewhat on your body size: The X Frame is just 18″ wide. If you’re a back sleeper, this isn’t that big of a deal. But if you sleep on your stomach, your arms and shoulders are going to end up over the sides of the X Frame, likely resting on the floor of your tent but within your sleeping bag. If the weather is cold, you won’t have much insulation between your arms and the ground. (I’d combat this by spreading some clothes on the sides of the X Frame for extra insulation.)
You might like this little gem of an idea, though: Because the X Frame is so narrow, it will easily fit inside of your mummy bag. This means you’re not going to roll off of it in the night and crowd your buddy in your backpacking tent. I tried it, with mixed results — I had to pay attention to how I rolled around, simply because I had less room inside my already tight bag. Plus, the feel of the pad isn’t fantastic on bare skin. Not bad, I just personally found it annoying. If you sleep in long underwear, you might really like this option, though.
Inertia X Frame Is Fantastic for Minimalist Backpackers
Personally, I tend to pack a larger air mattress — at least 24 inches wide and 72 inches long. The downside for me is the weight. I tell myself that a blissful night’s rest is worth the poundage, but as I get older, I’m starting to wonder. Might super light-and-lean be smarter?
Ultralight packers already know their own answer: They go light. For them, the Klymit Inertia X Frame should be a full-length cushion of awesomeness.
For the rest of us, Klymit has another answer: The Klymit Static V2. Named after its V-chamber design, it’s 23-inches wide, 72-inches long, and 2.5-inches thick. At twice the weight of the X Frame, the Static V is just 16.33 ounces — a little over a pound. To me, 7 extra ounces make it a winning compromise of weight, comfort, and cost — check out my full Static V2 review for more detail.
But hey, to each their own, right?
Get Klymit Pads at Amazon:
- Klymit Inertia X Frame [also available direct from Klymit]
- Klymit Inertia X Frame Military Recon version
- Klymit Static V2 Air Pad
- Klymit Static V Air Pad
- Klymit Static V Air Pad Insulated version
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