A-B1843729-AI VALVE-EXHAUSTOne New Aftermarket Replacement Exhaust Valve Fits Briggs and Stratton (B&S) Small Engines This aftermarket replacement exhaust valve fits select Fits Briggs and Stratton small engines used in lawn mowers, riding mowers, and outdoor power equipment. The exhaust valve seats in the cylinder head and controls the release of combustion gases from the engine cylinder, playing a critical role in maintaining compression, engine efficiency, and long term