The Brand Felt Ltd. Boot Liners 814 GWR with 3 layers of protection, 10" Height Wool Radiantex, 18% wool felt, 77% polypropylene, 5% miscellaneous fibers 8mm thick 3 layers of space age technology, heel reinforcements, ski doo boot style High-performance insulation, excellent heat reflection, and moisture wicking Excellent heat reflection, and moisture wicking