Banjo Planetary Geared Tuning Machine Pegs 4 - Nickel These brand new beautiful Tyler Mountain nickel planetary geared machines with pearlized plastic buttons will look great on your instrument. The shaft size of these are 9.5mm and include all the hardware you will need for installation. This is for one set of 4 nickel machines. Planetary Machine gear ratio: 4:1 3/8" shaft size; Fits 1/2" TO 5/8" inch pegheads