A sample from the products for the Rear Brake Caliper(cb1000 R) include: Retainer, Boot B, O-ring,2.5x1.5, Pin,bolt.
The O-ring,2.5x1.5 is the cheapest item from this partsfiche.
This schematic depicts all components used in the Cb1000ra 2010 (a) European Direct Sales Rear Brake Caliper(cb1000 R) partslist.