perfect for USA made electric guitar/bass/amplifier/effect pedal etc. Inch size, fine 24 splines, will fit most American made 6mm (15/64 inch) split shaft potentiometers like CTS/Fender/DiMarzio/Bourns, will NOT fit metric size potentiometers like Alpha Made of plastic, aluminum top Colour:Black & White Material:Plastic, aluminum Size:Inner hole diameter:6mm (15/64 inch), height:16mm (5/8 inch), base outer diameter:29mm (1-9/64 inch) Package Contents: 24 x knobs (2T+2V) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.