Thank you very much for viewing. This is a "Treble Bezel for Rickenbacker 4001/4003". By replacing it with the rear pickup cover of a Rickenbacker 4001 or 4003, it becomes a finger rest without any modification to the body. In addition, it gives a neat impression around the bobbin. Furthermore, the absence of a cover on the top of the pickup makes it easy to adjust the pole pieces. It is made of carefully processed ABS resin. It fits 4003 and 4001 models from the 70s onwards. It may also fit other Rickenbacker models that have the same pickup cover shape as the 4003 and 4001. For Greco and Fernandes, slight modification of the PU frame of this product with a file may be required. (Adjustment is easy because it is made of resin.) *Please search the internet for installation and adjustment methods. Please purchase only if you agree to no claims and no returns.