This is a replacement bell washer, a flat washer that can be used with a wide range of various types of lawn and garden equipment. The inner dimension of this washer is 0.40 inches, while the outer dimension is 0.88 inches. Washers are typically used as a way to help ensure a tight connection when used with bolts or screws. They will also help to distribute the pressure of the connection and reduce the risk of corrosion. Washers will also provide some protection from damage during installation. Washers could need to be replaced for any number of reasons. In some cases, they might have become corroded or worn down over time. This could mean they no longer provide a solid and secure connection. Other times, the washer could become lost while working on the machine. Owners should always be sure that they replace any lost or damaged washers right away. Not using washers can reduce the lifespan of the machine. This is a genuine OEM bell washer that is sold individually. It is typically used in lawn mowers, snowblowers, tillers, leaf blowers, string trimmers, log splitters, wood chippers, edgers, and chainsaws. It is compatible with Craftsman, Cub Cadet, Ryobi, Troy-Bilt, Husky, Murray, Yard Machines, MTD, Huskee, Montgomery Wards, Bolens, Yard-Man, Turf King, and MasterCut brands.