The RAM® Cable Manager with AMPS Hole Pattern for Electronic Mounts (RAP-403U) creates an integrated route for electrical wiring and cleanly covers installation holes. A great addition to any surface mounting application. It's made of glass filled nylon which has the benefit of creating a barrier between the RAM® Surface Mount and the attachment area; minimizing vibration while reducing fiberglass and gel-coat damage. This item will work with any of the 2-5/8" round plates with AMPs hole pattern.