This bundle includes the Alpine R2-A75M Mono Subwoofer Amplifier and the Alpine RS-W12D4 12-inch Shallow Subwoofer. The R2-A75M features a compact design with 750W power, Class D circuit, and one-sided terminals for easy access. It offers a reduced footprint and top panel controls for convenience. With dimensions of 11.1” W x 2.17” H x 6.5” D, it provides 500W RMS x 1 @ 4Ω, 750W RMS x 1 @ 2Ω power output. The RS-W12D4 boasts an ultra-shallow design, 20mm excursion, and 600W RMS power handling with a 4” voice coil. Key features include the Gen2 DD Linear Magnetic Circuit and neodymium magnet. Its tech specs include a mounting depth of 3.25”, X-Max of 20mm, and a frequency response of 26Hz – 200Hz. The subwoofer also has a sensitivity of 81dB, nominal impedance of 4Ω, and Thiele-Small Parameters like 29 Hz Free Air Resonance and 20mm Linear Excursion. Enhance your audio experience with this dynamic bundle that combines power, performance, and precise bass control in a compact and efficient design, ideal for upgrading your car audio system.