Class D Technology 5/4/3 Channels Waterproof lP66 MOSFET power supply 4-Layerconfurmal coated PCB assembly Variable gain control Turn-On/Off muting drcuiby(soft mute) Ground loop isolation input circuit and high-level speakerinp Bass Boost Adjustment - 0-12d8@50Hz High Pass Crossover{12dB/0ct) - Variable 15-250Hz (FR/RR) - 20kHz Low Pass Crossover (12dB/Oct.) - Variable 35-250Hz (SUB) - 20kHz Fuses: 40A x 2 (ATC-type)