The Alpinestars Race v4 pants are lightweight and offer high breathability and flame-resistance properties. This Formula 1 specification tech base layer incorporates a relaxed fit for comfort when wearing under a driving suit. Soft-touch textile for feel and enhanced comfort. Natural viscose fiber with unique thermal insulation and flame resistance properties that help prevent heat stress. FIA 8856-2018 and SFI 3.3 homologated.