Gear Review: Klymit Insulated V Ultralite SL Air Mattress

Klymit Insulated V Ultralite SL air mattress.
Klymit Insulated V Ultralite SL air mattress.

Insulated Air Mattress
Klymit Insulated V Ultralite SL
$120, 1 lb.
One size

Air mattresses for backpacking vary significantly in a few ways: comfort, price, weight, and packed bulk—and you often pay more for better comfort or low weight and bulk. But the Klymit Insulated V Ultralite SL bends that rule. So I took this relatively affordable air mat on a three-night, 39-mile backpacking trip in Wyoming’s Wind River Range in mid-September, and camping in Idaho’s City of Rocks in spring, to see whether sleeping on it proves as sweet as its price.

With fat, V-shaped air tubes running down the mat’s center, standard dimensions of 72×20 inches tapering to 18 inches at the foot, and 2.5 inches of thickness, the V Ultralite SL was comfortable even for a side sleeper like me—my hipbones never dug into the ground. Square air tubes along its edges keep its perimeter stable, so that I never slid or bounced off it. Not surprisingly, for comfort it compares with some air mats of similar thickness, but not with the most cush backcountry mats out there. However, comparing it against two of my favorites for sleeping on, the Big Agnes Insulated Air Core Ultra is cheaper but heavier and noisier, and the Sea to Summit Comfort Light Insulated is heavier, bulkier when packed, and more expensive.


Klymit Insulated V Ultralite SL air mattress.
Klymit Insulated V Ultralite SL air mattress.

The R-value of 4.4 gives it a higher warmth rating than most three-season air mats—but flat spots between the V-shaped air tubes in the mat can allow for cold spots if you’re on frozen ground; consider this a warmer-than-average air mat for cold sleepers on three-season trips. The synthetic insulation is noticeably quiet—a relief for anyone who’s rolled around on an air mat with insulation that crunches with every movement (or shared a tent with someone who’s on one)—and it delivered all the warmth I needed inside a tent on September nights in the 40s Fahrenheit.


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Klymit Insulated V Ultralite SL air mat.
Klymit Insulated V Ultralite SL air mat.

The valve twists to open and close, and conveniently can be pushed in to seal it while inflating, so that air doesn’t leak out while you’re drawing your next breath. Inflating it requires 12 strong breaths, which is faster than some air mats. The 20-denier ripstop polyester fabric helps keep it fairly lightweight for an air mat of these dimensions—but that fabric is about as thin as you’ll find in even the lightest air mats, so be careful with it. (Fortunately, Klymit offers a lifetime guarantee. In fact, I returned the first Insulated V Ultralite SL that I received because I could not detect an apparent slow air leak, but Klymit immediately sent me a replacement that has not leaked.) The Insulated V Ultralite packs down to 4.5×7 inches, comparable to many competitors with equal inflated dimensions.

In today’s market of deluxe, super comfy, compact backcountry air mats, some of which cost upwards of $200, the Klymit Insulated V Ultralite SL delivers good comfort and competitive metrics in weight and bulk at a good price—albeit with potentially less durability.


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If you’re on a tighter budget, check out the Klymit Insulated Static V Lite ($95, 1 lb. 4 oz., R-value 4.4), which is also 2.5 inches thick, but 23 inches wide, as well as slightly heavier and bulkier when packed at 5×8 inches. Or if you plan to only camp in mild summer temps and want a real bargain, Klymit’s uninsulated Static V air mat ($55, 1 lb. 3 oz.) has the same inflated dimensions as the insulated version and an R-value of 1.3.

BUY IT NOW You can support my work on this blog by clicking either of these links to purchase a Klymit Insulated V Ultralite SL at or


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See all of my reviews of air mattresses and all of my reviews of backpacking gear at The Big Outside. See also my related articles “Pro Tips For Buying Sleeping Bags” and “10 Pro Tips: Staying Warm in a Sleeping Bag.”

NOTE: I tested gear for Backpacker Magazine for 20 years. At The Big Outside, I review only what I consider the best outdoor gear and apparel. See categorized menus of all of my gear reviews at The Big Outside.

—Michael Lanza


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