The Swing Arm/chain Case is made up of components including this Arm Assy.,swing which is the most expensive.
In this schematic the "Screw,flat,5x4.5" is used most often.
A sample from the products for the Swing Arm/chain Case include: Washer,6x9, Arm Assy.,swing, Mark,tire Caution, Dust Seal 22x29x4.