Alpinestars Tech ZX Fire Resistant Racing Boxers - FIA 8856-2018The Alpinestarts Tech ZX Underwear is developed using LENZING FR, a flame resistant viscose fiber produced through a sustainable process. The fabric is thin, lightweight, and designed for a soft, comfortable feel against the skin. Based on materials and construction used in Formula 1, It is certified in accordance with the FIA 8856 2018 homologation, and the underwear is intended to be worn under standard racing layers, helping to reduce discomfort