This is a tremolo unit removed from an 80s Tokai Silver Star. The mounting hole pitch is 10.8mm. Included accessories are the arm and springs. The block is one-piece and cannot be removed. The springs are Raw Vintage RVTS-1, and while the thickness is about the same, these are softer. These parts were removed from a guitar from about 40 years ago, so there are some scratches, but they are Japanese-made, so-called "Japan vintage" parts. They have an atmosphere that new parts don't have. If you have any questions, please feel free to comment.