A-B1555734-AI VALVE-THROTTLEOne New Aftermarket Replacement Throttle Valve Fits Briggs and Stratton (B&S) Small Engines This throttle valve (valve throttle) is a carburetor component that regulates airflow and controls engine speed in Fits Briggs and Stratton small engines commonly found in lawn mowers, riding tractors, and other outdoor power equipment. Replacing a worn or damaged throttle valve restores proper throttle response and smooth engine operation. Specifications