The Ionosphere 5.5 Sleeping Pad is Rab's warmest air mat for winter environments. Its polyester-based, Stratus R insulation is made all the warmer with the TILT reflective film, and water resistance helps the pad retain its air in damp tents. Designed with a textured print, this pad works with oversized outer chambers to keep your sleeping bag centered. A 2-way valve keeps the pad low-profile, letting it pack down to the size of a large water bottle. Rab included a stuff sack that doubles as a pump for breath-free inflation.