... sciatica,and strain or lumbarUsage:Cold compress:Use after put in the ice box or freezing box(minus ... hot water heat itMaterial:outer material:PVC or PE+nylon or nylon+PVCgel inside: CMC (Carboxy MethyI ... s design in all of products:· biological ice bags,· ice box,· ice cube bags· cold and hot packs,· ... facial masks,· cool scarf/belts,· bottle coolers,· ice cooling mat· cool pet mat/clothes,and other ...