Studded Motorcycle Drivers Backrest to Fit Corbin Seats - 7" high x 7" wide STUDDED Motorcycle Driver Backrest 7" wide X 7" high Fits Corbin and other seats that accept a backrest with a 5/8" square stem that is 4.5" long. Pad angle is adjustable and has 2 inches of foam padding for comfortable back support. Our larger 10" x 12" studded backrest is also available.