Alpine MRP-M450 Mono subwoofer amplifier 220 watts RMS x 1 MRPM450 mono subwoofer car amplifier 220 watts RMS x 1 at 4 ohms (400 watts RMS x 1 at 2 ohms) variable low-pass filter (50-200 Hz, 24 dB/octave) tuned Bass EQ (0-12 dB bass boost at 50 Hz) subsonic filter (15 Hz, 24 dB/octave) MOSFET power supply CEA-2006 compliant STAR Topology (minimizes internal noise and prevents ground interference) speaker- and preamp-level inputs gold-plated screw terminals fuse rating: 20A x 2 8-gauge power and ground leads recommended — wiring and hardware not included with amplifier 9-3/4"W x 2-3/8"H x 9-9/16"D warranty: 1 year