Brake shoes are arc shaped to fit to the inside of a brake drum. Each shoe pivots on its own "anchor pin" retained in a bore in the brake spider. There are two types of brake shoes, open-anchor and closed-anchor. This means that the anchor end of the shoe where it forms the pivot either is full-circled or half a circled. Shoes are retained at the anchor end and S-cam end by springs, this is done so the brake shoes can be clamped down and also to have the brake shoes return to original position after they have been actuated. On the anchor side, there is two springs called "Retaining springs", and on the s-cam side there is only one spring called the "brake shoe return spring". A roller is retained by a clip spring or pin on the shoe at the S-cam end. In order to remove the brake shoes, one needs to remove the retaining springs, starting with the "brake shoe return spring" on the S-cam end, allowing the bottom shoe to hang, and then removing the "retaining springs" on the anchor side.