When you're sleeping outdoors and temperatures drop below freezing, the Big Agnes Oak Street Insulated Air Pad includes Primaloft Synergy insulation to keep you comfortable. The lightweight Primaloft Synergy insulation is laminated to the top of the pad and only adds 1-2 ounces of weight over the non-insulated Oak Street air pad. The insulation is soft, high loft, compressible, and durable, providing valuable added comfort while still allowing the pad to pack down to the size of a coffee can. Durable nylon ripstop fabric and an internal polyurethane coating protect the pad from abrasions, and the PU coating also improves the functionality of the pad. The EZ Flate inflation valve makes inflating the pad a breeze: it features an integrated two-piece plastic cap with a free-spinning top that allows you to close the valve by spinning the bottom portion while keeping it in your mouth so you can seal it shut with minimal air loss. The pad inflates to a cushy 3 inches in the middle and 3.5 inches in the outer air chambers. The larger outer chambers keep you cradled in the middle, and the pad's I-Beam construction (with full-length side-by-side air chambers) makes it quick to inflate and deflate, reduces cold spots, and provides consistent cushioning and air flow. When you're done using the pad, you can pack it into the included stuff sack. The stuff sack comes equipped with a small repair kit so you're never left roughing it on bare rocks or branches and without insulating comfort underneath you.