Made from thin polyurethane, skin systems offer the most realistic top and front hairline appearance. You have your choice of a few different skin options including the Micro Skin, C-Thru Skin or — the newest and most innovative skin on the market. Introducing the new HD Skin These super-thin natural poly systems use v-loop ventilation rather than hand-tied knots, giving them the growing-right-out-of-your-scalp look.