HD600/44 channel amplifer 150 watts RMS x 4 (rated power from 1. 5 to 4 ohms) 300 watts RMS x 2 bridged (rated power from 3 to 8 ohms) variable high and low pass filter (50 500 Hz 12 or 24dB octave) subsonic filter and output polarity control removable power and speaker plugs Class D amplifier design MOSFET power and output stages differential balanced inputs eliminate noise from your vehicle's electrical system preamp outputs 4 gauge power and ground leads