#650DB 3/8" dia RoboStrut Gear Door Mounting Brackets
#650SA Sleeve Adapter 3/8" to 7/16"
#660DB 7/16" dia RoboStrut Gear Door Mounting Brackets
#660SA Sleeve Adapter 7/16" to 1/2"
#670DB 1/2" dia RoboStrut Gear Door Mounting Brackets