Bass control knob for car audio amplifier universal fit for most vehicles1、Wide Range of Applications: Our car bass controller knobs are extensively used in car audio systems, which is universal fit for most cars. 2、Volume Adjuster: This car bass controller an be used to adjust amplifier power levels, stereo, equalizer or cross volume from the dashboard or other location. 3、Provide More Convenience: You can quickly control or adjust bass gain, volume and level from the front seat or a distant location through this bass controller. 4、Easy to Operate: You can control the bass by adjust gain or frequency through rotating the button of the controller, which is very simple and efficient. 5、Enjoy Different Music: By installing a subwoofer level control or balancing a multiple amplifier, different frequencies can be achieved, which allows you to have more different experience when listening to music.