Tokyomods 99-004 Mag Hot Start Nut (Billet) 4 STROKE APPLICATIONS: ALL KEIHIN FCR CARBURETORS Honda CRF150R, CRF250R/X, CRF450R/X; Suzuki RMZ250, RMZ450; Kawasaki KX250F, KX450F; Yamaha YZ250F, 450F; KTM 250/450/505/530