This is a genuine Ryobi replacement part. The spring washer is designed by the manufacturer for use in power tools such as miter saws, routers, and planers. This part is made of metal, and may be found in various locations in the machine, depending on model. Please be aware that there are different washers used in the machine. Refer t...Read moreo the parts diagram to be sure of ordering the correct part. You may require a screwdriver when replacing this item. This part is sold individually.