Hifonics ZRX1816.1D Zeus Mono Class-D Subwoofer Amplifier, 1800-Watt Illuminated Hifonics Badge SPC - Simpatico Coil Design, HSMD - Hifonics Surface Mount Design PWM MOSFET Power Supply for Maximum Current Levels DC, Short Circuit, Thermal and Overload Protection A classic Hifonics aluminum heatsink with a Zeus 1800 Watt, 1 ohm stable, Class D mono subwoofer car audio amplifier.