Alpinestars STELLA TECH ZX bra is made from LENZING FR, an innovative, sustainably produced viscose fiber that provides exceptional flame resistance and protection against heat transfer. This Formula 1 derived undergarment is extremely lightweight and thin, and is designed to be incredibly soft to the touch, offering greatly enhanced comfort when worn underneath mandatory underwear layers. Certified to FIA 8856-2018 homologation standard for personal underwear.