American Bass 4000W Max Class D Amplifier Phantom Micro-Technology Class-D Technology, High Effi ciency and Fast Response. Variable Bass Boost. Low Pass Filter and Subsonic Filter. 4-Way Protection. Noise Free Design. RoHS Compliant. Heavy Duty Aluminum Heatsink. 1 x 4000 Watts MAX @ 1 Ohm. Dimension: 10"Lx 7.5"W 4"H. Weight: 7.3 Lbs.