Universal Bass Control Knob Bass Volume with Extension Cable for Car Amplifier

brand new never used WORKS PERFECTLY - This amplifier bass volume control knob is specially designed to solve the problem of the car audio main control board and subwoofer volume out of sync, so that the music achieves the ultimate effect. EXTENSION CABLE - The bass control knob connector cable is approximately 12.7 feet. It is usually installed in the free position of the driver to provide easier control of the volume.