The Ariens Company 21547281 Lawn Tractor Flat Idler Pulley helps maintain proper belt tension and smooth operation for compatible lawn tractor mower systems. It works by guiding the belt path and maintaining consistent pressure on the belt, supporting efficient power transfer and reducing belt slippage. Made to replace a worn or damaged idler pulley, it helps restore reliable mower pe... https://www.wholetoolbox.com/ariens-company-21547281-lawn-tractor-flat-idler-pulley/21547281.html