Designed for Formula 1 racing, the Alpinestars ZX Evo v2 line of fire-retardent underwear is extremely light and thin, without sacrificing comfort or protection. Through the use Alpinestars' proprietary Lenzing FR fabric, the ZX Series uses a revolutionary tubular knit construction, making the Alpinestars ZX Evo v2 balaclava nearly seamless. This also offers a compression like fit for comfort, helping to reduce bunching when under the helmet. Double layers in the front help improve protection, while Flat Seam construction reduces pressure points and improves strength. Available in a single, open-eye opening. One size fits all.