Yamaha John Hagstrom Model This signature model is difficult to obtain in Japan. It has been used a few times and is in good condition. ・Rim Inner Diameter: 16.45mm ・Rim Thickness: Standard ・Rim Contour: Semi-round ・Cup Depth: Standard ・Throat Diameter: 3.72mm ・Backbore: Standard (Reference: YAMAHA USA)