Class-A/B Marine Bluetooth Amplifier (No head unit required) & 3 m Wired Remote with 3-color LED indicator (sources – USB/AUX/Bluetooth). Wired Remote with S-terminal connector, please ensure the cable connection is always tight. Wired remote can be immerged in water, Silicone Gasket to protect the Black Box from water splashing. Rustproof Aluminum heatsink with white painted finish. All screws and mounting kits are made from Stainless Steel. Drive Max Power Output 180W into 4 Channels (suggests to work with 4 ohm 45W speaker). Real data for your verification. USB Charging 5V 1A / Frequency Response: 20Hz – 20KHz / 15 Amp Maxi Fuse.