1. These knobs are designed to fit a 6mm/0.23Inch shaft hole diameter,making them suitable for a wide range of guitars and basses. 2. The screw type design ensures a secure fit and easy adjustment. 3. Each knob providing ample for a comfortable grip and precise volume control. 4. The classic black color with a silver-tone top adds a stylish touch,enhancing its overall aesthetic while maintaining functionality. 5. The set includes 15 potentiometer control knobs and 15 counting scale sheets. Fixed :side screw Inner hole material:copper Product name:potentiometer knob cap Rotation angle:180 Service life:about 1,000,000 times Colour:Black Material:Aluminum Alloy Package Contents: 15 * 0-100 Scale Sheet 15 * Potentiometer 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.