Replaces the stock handlebar mounted start switch and relocates it onto the throttle housing. By removing the strap mounted switch handlebar changes are faster and easier. It also creates more space for handguards, lap timers and other handlebar mounted accessories. Installation is simple and explained in the enclosed instructions by splicing in two wires. NOTE: CRF450R ’09-16 & CRF250R ’10-16 kill button requires LED light M05-750031. KX450F ’12-21, KX250F ‘14-21, RMZ450 ‘15-21 & RMZ250 ‘16-21 launch control requires LED light M05-750031.