Description The product is to control the gain level / volume of devices connected to the car stereo, such as speaker, amplifier, bass, etc. It is manufactured with premium material for durable and long lasting use. Excellent workmanship its high practicability. Strict quality inspectation system insures you premium product and safe usage. Great and helpful accessory for your car. Features - ColorMulti - Material: Plastic. - Size: 25x4x3cm / 9.8x1.6x1.2inch(LxWxH). - The product is to control the gain level / volume of devices connected to the car stereo, such as speaker, amplifier, bass, etc - The controller enables you to adjust the gain level or volume of the device conveniently while driving - Simply connect the RCA output connector to the car stereo and the input RCA connector to the device, no additional wires are required - Made of high-quality chipset and elegant metal casing, perfect transmission of music signal - Length of the product: 27 cm.Package list: 1 x set of Car Stereo Amplifier Gain Level Bass Audio Volume Control Knob with 2 RCA Connector