Usage Tips:Easily adjust the volume of your car amplifier and subwoofer with this convenient remote controller. Manage your audio system while on the road. Customize the sound output to suit your preferences and enjoy a listening experience. Designed for car owners who appreciate quality sound, this versatile volume controller is compatible for various car audio systems and subwoofers. Perfect for those seeking to optimize their in car audio experience. Whether you are driving in on the highway, or going on a long trip, this remote volume controller is a practical addition to your car. Adjust the volume easily and safely without distractions, ensuring a pleasant journey. Take control of your car audio system with this remote volume controller. Fine tune the amplifier and subwoofer volume to create the perfect sound for your Upgrade your in car entertainment and on the road. Colour:Black Material:ABS Package Contents: 1 x Amplifier Bass Knob 1 x 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 a little different from the real thing. The measurement allowed error is 1-3cm.