The Rear Brake Caliper is made up of components including this Caliper Assy, Rear 2 which is the most expensive.
This schematic depicts all components used in the Xj900s 2002 4kmd Holland 1a4km-300e1 Rear Brake Caliper partslist.
The most reasonably priced component used on the Xj900s 2002 4kmd Holland 1a4km-300e1 Rear Brake Caliper is the Bolt(3ef).