Diameter: 38mm Height: 22mm Aluminum Solid Knob Volume Potentiometer Knob 2021 New Silver Black Knob Hifi DIY Kits Big Size Quality Aluminum Knob Volume Switch Dia38 H22 Materials: Aluminum Color: Black / Silver All aluminum solid, surface anodized treatment,CNC Diameter: 38mm, height: 22mm Potentiometer aperture: 6mm With installation screws MOQ 50 pieces for custom size and color.