A-B1696750-AI TUBE-BREATHEROne New Aftermarket Replacement Tube Breather Fits Briggs and Stratton (B&S) Small Engines This aftermarket replacement tube breather Fits Briggs and Stratton (B&S) small gasoline engines used in lawn and garden equipment. The breather tube is part of the engine crankcase ventilation system, routing blow by gases out of the crankcase to prevent pressure build up and oil contamination that can cause rough running, oil leaks, or accelerated engine wear.