FastServ?s Throttle Body, Carb and Choke Cleaner is a powerful combination of concentrated solvents that is specially formulated to remove dirt, gum, and varnish deposits that tend to build up on the moving and sealing surfaces of engine carburetors, heat valves and automatic chokes, throttle bodies, PVC valves, and throttle injectors. Periodic use on cars, trucks, boats, lawnmowers, etc., will keep engines clean and more fuel efficient. This cleaner can be used on running engines. Formulated for high performance without the use of ozone depleting chlorinated solvents.