Pyle 2-Channel Marine Amplifier Receiver - Waterproof and Weatherproof Audio Subwoofer for Boat Stereo Speaker & Other Watercraft - 400 Watt Power, Wired RCA, AUX and MP3 Audio Input Cable WATERPROOF & WEATHERPROOF: The audio amplifier is waterproof with its marine grade protection. It has a rugged construction and integrated power wiring harness to combat weather conditions as well POWERFUL 400 WATT: This amplifier receiver is powerful with its 400 watt max. It has an anti-thump turn on and soft turn on or off to save energy. Comes with 2 to 4 Ohm speaker impedance and adjustable volume control 2 CHANNEL AMPLIFIER: Pyles PLMRMP1B_0 is engineered as a 2-channel marine amplifier that powers up any boat stereo speaker and is universally compatible too. It has wired RCA, AUX and MP3 audio input SHORT PROTECTION: Built with a heavy duty heatsink, thermal overload speaker short protection to protect the amp and your vehicle's electrical system from short circuit conditions. It has 10A fuse COMPACT AND LIGHTWEIGHT: The amp is compact with an exact dimension of 4.13'' L x 3.35'' W x 1.38'' H and lightweight with only 1.89 lbs. The frequency response is 10Hz - 40kHz