Sometimes, the extra weight associated with a more comfortable nights sleep pays for itself many times over. Built wider than their mummy shaped cousins, the Sea to Summit Comfort Plus S.I. Rectangular Mats are designed to maximise comfort and warmth for cool-climate treks. At 8cm thick and a winter rated R-Value, the Comfort Plus S.I. Rectangular Mats provide luxury in a packable size. A 30D stretch knit fabric is used on the top layer for a great next to skin feel, and a lightweight 30D polyester with extrusion laminated TPU is used on the base for increased durability. All Sea to Summits self-inflating mats feature our unique, multifunction reversible single valve, designed specifically for self-inflating mats. No more fighting re-inflation as you roll up your mat!