This is a genuine Skidoo OEM retaining ring, part number 503193439. It comes in a pack of two and is perfect for use with snowmobile engines. The brand is Ski-Doo and the manufacturer part number is 503193439. This item is listed in the Snowmobile Engine Components category and is part of the Engines & Components, Snowmobile Parts, and Parts & Accessories categories on eBay Motors.