This is a 3.5 milometer brass throttle slide for an AMAL MK-2 carburetor for a triumph motorcycle. The throttle slide controls air flow into the carburetor to mix with the fuel and keep the fuel in gas state. This keeps the fuel from flooding the float bow, and clogging the spark plugs. If you are having trouble with too much fuel(in liquid form) in your carburetor, than this may be your problem.