Please note these are not direct fit tuners for Fender bass, drilling new holes may be required for installing, please verify the dimension drawing before ordering. Mounting hole spacing is 1-9/64" across the top, 1-1/32" across the bottom, and 1-31/64 top to bottom (on center). 28:1 Tuning Ratio; Makes for a finer degree of control than lower ratios. Super light weight; Prevent slippage and help eliminate out of tune frequency, provide a smooth and precise tuning experience that will keep your bass in tune for longer periods; Includes bushings and mounting hardwares.