Pyrotect’s ultra thin innerwear base layers are designed for use with any driving suit. They are as soft as cashmere and as absorbent as cotton! The SFI rated bottom is for use as a base layer, but it is also designed so it can be worn under Nomex underwear for added TPP protection or under crew uniforms for added fire protection. The SFI label is attached. The Pyrotect Underwear Bottom is available in sizes from 2XS to 2XL.