Therm-a-Rest Prolite Plus Ultralight Self-Inflating Backpacking Pad Four-season self-inflating foam sleeping pad for winter backpacking and camping, ideal for sleeping in cold conditions Diagonal-cut foam offers more warmth than the typical vertical-cut foam with an R-value of 3.4 Expanding foam core is lightweight and compressible for easy packing; pad self-inflates and can provide firmer support with a few breaths Suited to ski touring and alpine excursions, the 1.5-inch thick mattress is an ultra-compact expedition sleeping solution Large size measures 77 x 25 x 1.5 inflated, packs to 13 x 5.1 inches, and weighs 31 ounces; stuff sack and repair kit included