Good luck trying to get a standard sleeping pad to fit and stay put in a hammock. For that reason, under-quilts have long been the go-to defense against cold while hammocking, but they’re often bulky. New solution: this uniquely shaped pad, which has four wings that contour to the hammock’s shape and sticky rubber grips that keep the mat in place. The pad’s synthetic fill and 4.4 R-value kept our tester toasty in 3°F temps during a cold snap in Virginia’s Jefferson National Forest. But he noted that, although it didn’t affect performance, the wings spilled over the sides of a single hammock and were a bit of a nuisance when climbing in and out. Caveat: All that warmth means high price and weight.