The pinion driver goes between the drive nut and the gear. This item is an original part from Tecumseh and Toro for use in lawn mowers. It is made of rubber and is available as an individual replacement part. When replacing this item a screwdriver and a socket set might be required during the installation process. Over time this part may break and will need to be replaced.
This is an authentic replacement part manufactured for use with lawnmower engines. The special gear is connected to the armature of the starter motor and drives the flywheel which spins past the ignition coil creating the charge that is sent to the spark plug. This gear is sold as an individual replacement part.