Engine idler pulley 807757T is for use on MerCruiser 4.3L, 5.0L, 5.7L, 6.2L and 8.2L sterndrive or inboard engines having a serpentine belt and made by General Motors. The pulley is made of long-lasting thermal resin. The bearing is molded into the pulley. When replacing the idler pulley, check the pulley support bushing and serpentine belt for damage or wear. Replace as necessary to help keep your engine running at its peak performance. The Quicksilver brand is the leader in delivering uncompromising engine oils, parts and accessories to the marine industry for over 65 years. Quicksilver is the premier supplier of Mercury Marine Original Equipment replacement engine parts, oils, and accessories, but also works to serve all Original Equipment brands in the marine and powersports industries. It has earned a loyal following by providing the highest quality products that are tested through some of the most rigorous environments and testing procedures. No aftermarket company comes close to the level of research and design as Quicksilver; buying Quicksilver is buying performance, protection and peace of mind.