- Warwick Parts, potentiometer knob for electric guitar or bass, knurled, cylindrical dome shape, diameter: 18 mm (0.7"), height: 18 mm (0.7"), suitable for split shaft potentiometers with knurled shaft (18 teeth, 6 mm (0.23") diameter), satin chrome finish, 1 pc. EUR 3.00 - See more - Buy online