Power Acoustik BAMF4500/5D BAMF Series Class D 4500-Watt 5-Channel Amplifier High-efficiency Class D Full Range Amp Mosfet Power Supply With Audiophile-grade Irtm Transistors Hybrid Aluminum Alloy Heatsink For Optimum Dissipation 2 Stereo & 4 Bridged Full Range Operation 1 Stable Monoblock Operation