This is a Mastery Bridge, known for its high precision. I bought it over 10 years ago, but during a live performance, one of the screws and springs that secure the saddles came loose and got lost, so I haven't used it and have kept it in storage. Therefore, the usage period was short, but it's missing a part (see the red circle in the photo). Would this be suitable as a replacement part, or for someone who already has the parts? Please note that it will be simply packaged. The legs may be disassembled for packaging. Included are one large wrench, and what I believe are two metal parts for USA models. Also included are the box and instruction manual, both of which are strangely labeled "M1" (see photos). I used this on a Fender Japan Jazzmaster. The innovative Mastery Bridge, with its unique shape and saddle structure, improves string slippage issues common with Jazzmaster, Jaguar, and Mustang saddles. Not only does it function well, but it also transmits string vibrations to the body without loss, resulting in a clearer and more powerful sound, achieving the best possible tone and improving sound quality.