Features: Gently rotate the control knob to adjust the volume. Different settings allow for customized sound output, providing a smooth and convenient user experience. Connect the RCA output of this controller to your amplifier, and connect the car stereo output to the RCA input of this unit. Ideal for subwoofer amplifier volume control. Designed to remotely adjust an amplifiers power level, stereo balance, equalizer, or crossover volume from the dashboard or other locations. Enables sub-woofer level adjustment and helps balance multiple amplifier setups. Compact design allows for flexible mounting options, placing control within easy reach. Fine-tunes the volume of any RCA line-level signal. Simple plug-and-play connectionsno additional wiring required. Specifications: 4 RCA ports: 2 RCA inputs and 2 RCA outputs Level control knob Frequency Range: 150Hz - 40Hz Volume Gain Range: 0dB to -12dB Dimensions: 48 x 56 x 41mm / 1.89 x 2.2 x 1.61 inches Material: Plastic Color: As shown in image Package Contents: 1 x Controller Note: Light reflection and differences in display screens may cause slight variations in color between the product image and the actual item. Measurement tolerance: +/- 1-3cm.