Outlaw Racing Billet Gas Fuel Cap CRF100 CRF150 CRF230 04-10 Reviewhttp://tinyurl.com/pwroxs6 Outlaw Racing Billet Gas Fuel Cap CRF100 CRF150 CRF230 04-10 Billet machined 6061-T6 aluminum.Gas resistant rubber seal.Tapered seal surface to prevent fuel leaks.