The Expander liner is made from a premium stretch knit poly-cotton, making it super stretchy and even warmer than a standard cotton weave liner. The stretchiness allows the Expander to move with you as you sleep, vastly increasing comfort and minimizing tangles. The knitted construction of the Expander Fabric means that they are manufactured without a side seam, eliminating a potential source of irritation and a wear point.

The anti-microbial treatment keeps microbial life, thus bad odors, at bay which also helps prolong the life of your liner and sleeping bag. The anti-microbial treatment won’t wash out of the liner and does not use nano-sized particles. The treatment is registered with the EPA.