This came off a 1989 KX 500 but I think it will work on most any 2 stroke bike. This gives you increased spark for better performance. This just plugs in to wiring that goes to the coil, very easy to use. just zip tie it up under the gas tank.I used this on my KX500 at Little Sahara and Fallon sand dunes and was never beat by anything. My buddies couldn't figure out why my bike kept beating thier CR500s.. $50.00…Cash Only !!!