Using PRIMALOFT Silver Insulation which is quick-drying, water repellency, heat retention, and highly compressible. 20 denier PERTEX QUANTUM AIR is used to wrap the insulation. Bore fleece is used for the ear part. Heat can be released by opening the top. NYLON 100% (PERTEX) padding POLYESTER 100%(PRIMALOFT) partly POLYESTER 100%