Boss Audio Mr800 2-Channel Mosfet Bridgeable Marine Power Amplifier. W/ Remote Subwoofer Level Control:. All Mr Series Amplifiers Feature A Unique Rubber Sealing Door Which Tightly Seals All Control Panel Openings When Not In Use. It Also Uses In-Line Weatherproof Connectors For All Input And Output Connections, Which Are Run Through Grommeted Openings In End Panels. Mr800 Marine Power Amplifier Features:. Max Power 2 Ohm: 400W X 2. Rms Power, 4 Ohm: 125W X 4. Max Bridged Power, 4 Ohm: 800W X 1. Signal-To-Noise Ratio: >102 Db. Thd: 0. 01%. Dimensions: 8-3/4" L.