Suitable for 4-pin line, 12V power amplifier equipment. Enhances your auto sound experience with this bass knob, a general car amplifier volume control designed for precise bass and volume adjustments. This knob features simple in/out connections for easy installation, allowing you to adjust gains and frequency without the need for additional wiring—ideal for ophiles seeking optimal sound quality. Suitable for music enthusiasts and professional sound producers who want convenient control over their car's o system while on the move. Whether on a long road trip or enjoying music during daily commutes, this bass knob ensures your sound is tailored to your preferences. The bass knob complements auto interiors with its design and offers a responsive interface for quick sound adjustments, making it an essential accessory for any auto sound upgrade. Head size: about 5 x 7 cm / 1.97 x 2.76 inches Cable length: 5 m Color: Black Material: Plastic Package Contents: 1 x Car Amplifier Volume Control Cable 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 to vary slightly from the real thing. Measurement allowance is +/- 1-3 cm.