The Simpson Endurance Racing Gloves feature 100% Nomex® construction for a SFI 3.3/5 rating. With a silicone inner and outer palm, flexible reinforced fingers, anti-fatigue pre-curved hand, elastic on the cuff with a longer gauntlet, and external seams they amongst some of the most comfortable driving gloves you may ever own. Please note these glovesrun a little small compare to other Simpson gloves, it's recommended you order a size larger than normal.