Sound Storm Laboratories AE140D AERO 4,000-Watt Class D One Ohm Stable Monoblock Amplifier with High/Low Crossover and Remote Subwoofer Level Control - Black/silver One OHM stable Class D monoblock Strapping capability allows user to strap two amps together for twice the power stable at 2 Ohms Remote Subwoofer level control MOSFET PWM (Pulse With Modulated) power supply Soft turn-on circuit