The Female Base Mount is part of the Quiver/Clamp Assembly. It is the plate that attaches directly to your compound bow. If you want to transfer your Retriever between two bows and don’t want to purchase an entire Quiver/Clamp Assembly, you could simply buy this plate, a Slab Nut, and 2 Z9 Mounting Screws. Then detach the assembly at the Thumb Screw and re-attach to the new plate.