The inner fabric of a product. In our sleeping bags we use DreamLite RP Nylon due to its downproof qualities and low weight. Cheaper sleeping bags use a cotton liner which some people find more comfortable but does absorb sweat. To prolong the life of a down sleeping bag you can use a sleeping bag liner made of silk or cotton. Our rock shoes feature a Cambrelle lining. Developed specifically for footwear Cambrelle linings draw sweat away from the foot much like a base layer garment would making you feel more comfortable.