"brand new and high quality\r\n\r\nFeatures:\r\nJust gently rotate the button of the controller. Different frequencies can make the song sound different. It feels very good and is very convenient.\r\nConnect the RCA from the output of this controller to the amplifier, and wire the car stereo output to the RCA input of this unit.\r\nGreat for a sub amp volume control.\r\nUsed to adjust an amplifier's power level, stereo, equalizer or crossover volume form the dashboard or other remote locations.\r\nAdds sub-woofer level controls or balances a multiple amplifier installation.\r\nCompact housing allows the unit to be mounted virtually anywhere so control is at the user's fingertips.\r\nFine tunes the volume of any RCA line level signal you to control.\r\nSimple in and out connections, no additional wiring needed.\r\nConnect the RCA from the output of this Controller to the amplifier, and wire the car stereo output to the RCA input of this unit.\r\n\r\nSpecification:\r\n4 RCA: 2 RCA input & 2 RCA output\r\nLevel control knob\r\nFrequency Range: 150Hz - 40Hz\r\nVolume Gain Range: 0db to -12db\r\nMaterial: Metal\r\nDimensions: 48x56x41mm/1.89x2.2x1.61inch\r\nColor: Black\r\nQuantity: 1 Pc\r\nNote: 1.Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid.\r\n 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!\r\n\r\nPackage includes:\r\n1 x Car Audio Regulator":