The Nike Hypercool Vapor 4.0 Skull Cap is designed to wick away sweat and keep you dry and cool throughout the game with its dri-fit fabric. Nike has provided the perfect head gear to have on under your helmet, whether its a CCM Tacks player helmet or a Bauer NME goalie mask. The strategically placed mesh panels improve breathability and work with the dri-fit fabric to keep you comfortable. This Nike skull cap is 80% polyester, 11% rubber, and 9% spandex.