Soundstream MR5.2000D Rubicon Nano 2000W Class D 5-Channel Marine Amplifier Rubicon Nano 2000W Class D 5-CH Marine amplifier High Efficiency Class D Full Range Amplifiers. 2-ohm Stereo & 4-ohm Bridged Class D Full Range Hybrid Aluminum Alloy Heatsink for Optimum Dissipation 12dB Bass Boost Increases Low Octave Harmonics MOSFET Power Supply w/ Audiophile Grade IRTM Transistors