Widely used in amplifier building, Fender/Squier Strat style and other similar style guitar bass It is a Universal Fitting design, fit fine spline and coarse spline split shaft pots like CTS and Alpha pots, does not fit solid shaft pots Inner hole diameter: 6mm(15/64 inch), height: 15.8mm(5/8 inch), outer diameter: 19mm(3/4 inch) Made of plastic, no screws hole