Unleash the power of your car audio system with the Universal Bass Control Knob! This ingenious device solves the frustrating issue of the main control board and subwoofer volume being out of sync. Strategically installed within reach of the driver, it offers effortless control over the volume, allowing you to fine-tune the bass to your desired level. The 4-pin crystal connector ensures seamless integration, while the 16ft extension cable provides ample length for optimal positioning. Crafted with pure copper core cables and high-quality insulated PVC protective wires, this knob guarantees durability and reliable performance. Experience unparalleled audio bliss and take command of your car's bass with this must-have accessory. 100% QUALITY GUARANTEE ensures your satisfaction.