The Briggs & Stratton 694039 Camshaft controls valve timing for smooth and efficient engine performance during operation. Designed as a replacement camshaft component, it fits compatible Briggs & Stratton engines to coordinate the opening and closing of intake and exhaust valves within the engine system. It works by rotating in sync with the crankshaft to control valve movement during combustion cycles. This supports reliable engine timing, smoother performance, improved combustion efficiency, and dependable equipment operation.