The Briggs & Stratton 499612 Gear-Ring is a replacement engine ring gear designed to provide reliable starter engagement on compatible engines. It works by meshing with the starter gear during engine startup, allowing the flywheel to rotate and initiate the combustion process. Replacing a worn, chipped, or damaged gear ring helps restore dependable starting performance and proper enga... https://www.wholetoolbox.com/briggs-stratton-499612-gear-ring