i520.4 - Precision Power 4-Channel 520W RMS 1040W Max Class D iON Series Full Range Digital Stereo Bridgeable Amplifier i520.4 - Precision Power 4-Channel 520W RMS 1040W Max Class D iON Series Full Range Digital Stereo Bridgeable Amplifier RMS Power Rating: 4 ohms: 100 watts x 4 chan. | 2 ohms: 130 watts x 4 chan. | Bridged, 4 ohms: 260 watts x 2 chan. Pulse Width Modulated MOSFET power supply Low-Heat producing circuit Dimensions: 5-5/16"W x 9"L x 1-11/16"H