Rockford Fosgate 500 watt amp, some scratches but performs flawlessly. Rated at 125W X 2 channels at 4 ohm. Or 250W X 2 at 2 ohms. Or mono at 500W X1 at 4 ohm. This is manufacturer ratings, the actual output is about 30% higher. Manufacturer does not recommend 1 ohm loads, but in many tests it has performed well at that impedance.
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