Description:Made of phenolic plastics , aluminum, solid and durable. knobs specially used for potentiometers.Great as speaker control knob and amplifier knobs and for general electronic usageSmooth surface, fit most potentiometer, easy installation.Convenient to use, great accessories for DIY or to replace broken ones.Specification:Material: phenolic plastics , Aluminum Knob Diameter: 29mm / 1.14"Knob Height: 18mm / 0.71"Fits 6mm shaft pots Package Content: 4 Pcs x Knobs