100k Volume Control Variable Resistor Potentiometer 100 k 3 pin Controller for DIY Amplifier Kits and Home Theaters 100K Audio Potentiometer Pot Volume Controller for Home Theaters and Amplifiers This is a Volume Control Amplifier Knob made of Aluminium Alloy which is rugged and very good looking. The dimension of the knob is 30 x 16 mm with a 6mm shaft. These Button Mould knobs can be used to control the volume of a stereo or to control the speed of a motor.