Used to adjust an amplifier's power level, stereo, equalizer or crossover volume form the dashboard or other remote locations Adds sub-woofer level controls or balances a multiple amplifier installation Compact housing allows the unit to be mounted anywhere so control is at the fingertips Simple in and out connections, no additional wiring needed Connect the RCA from the output of this Controller to the amplifier, and wire the car stereo output to the RCA input of this unit Great for a sub amp volume control Specification: Size: (approx.)80*70*40mm/ 3.15*2.76*1.57inch Adds a Mounted Sub-Woofer Volume Control 4 gold plated RCAs (2 RCA input & 2 RCA output) Level control knob Frequency 150Hz - 40Hz Gain 0db to -12db Package Includes: 1 x Audio Curcuit Noice Isolator