This is a genuine replacement part sourced directly from the manufacturer. The ball bearing is commonly found in power tools from Skil and Bosch, such as drills, jig saws, and rotary shears. This part is made of metal, and is generally used to allow components to spin freely. It may be found in various locations in the machine, dependi...Read moreng on model. Please be aware that there are different bearings used in the machine. Refer to the parts diagram to be sure of ordering the correct part. You may require a screwdriver or Allen wrench when replacing this item. The ball bearing is sold as an individual replacement part.