The name says it all. The maximum gram-shaving mat for the mountains. InsulMat mix their proven weight-saving techniques of cutting and drilling the foam to attain high R-Values where they count. In the upper 122 cm (48) body core section they use lateral drilling to reduce weight and bulk while reducing the surface-to-surface convection cells from developing within the mat. In the foot area they apply their matrix die cut-foam to substantially reduce weight and bulk further. A true lightweight winter mat.Available in 3/4 length & full length.'