The retaining ring goes next to the washer and the roller. This part is available individually and is made of metal. This is an original Simplicity and Snapper part for use in snowblowers, tractors, and mowers. During replacement, it may require a set of pliers and a screwdriver to help install this part correctly. It may become broken and will need to be replaced.
This is an authentic Simplicity replacement part. The idler pulley is designed by the manufacturer for use in lawn mowers and snow throwers. This part is made of metal, and is used to adjust tension on the V-belt. You will require a wrench when replacing this part. This item is sold individually.