Skar Audio MSK-200.1D Monoblock 420W Class D Ultra Compact Subwoofer Amplifier MSK-200.1D - Skar Audio Monoblock 218W RMS 436W Max MSK Series Mini Amplifier RMS Power Rating: 4 ohms: 87 watts x 1 chan. | 2 ohms: 150 watts x 1 chan. | 1 ohm: 218 watts x 1 chan. | 1 ohm: 436 watts x 1 chan. max Wired remote bass level control included RCA output for daisy chaining multiple amplifiers Dimensions: 4-15/16"W x 6-5/16"L x 2-1/4"H