The Sparco Shield RW-9 series of underwear offers the lightest weight of any technical, fireproof underwear on the market today! Using a circular-spun fabric layout, seams are kept to a minimum, helping the RW-9 T-Shirt disappear underneath your driving suit, creating an additional layer of protection that can hardly be felt. The technical material is designed to remove sweat from the skin as quickly as possible for superb breathability. The short-sleeve T-Shirt features additional inserts in the back, armpits and chest for additional breathability and comfort.