This is a replacement spacer for walk-behind lawn mowers, riding lawn tractors, snowblowers, and other outdoor machinery. The spacer prevents parts from grinding together and wearing down. This spacer fits over the axle areas and is a small, flat, metal ring.Over time and through wear and tear, a spacer can go bad or get bent. This is also dependent on frequency of use. For equipment used maybe once a week (or month, depending on the season), replacing a spacer may never be a concern. For machines used more frequently, it may be a rather minor fix. Replacing the spacer is simple, and requires a screwdriver, pliers, wrench, and a pair of durable gloves. The replacement requires some disassembly of the lawn mower and its inner workings.This is a genuine OEM replacement spacer. This part is compatible with over 150 products and machines. This part is sold separately.