Surface-mount LED underwater lights include three series 9W ,18W and 27W. Different light colors available for each series. All lights use marine grade SS316 housing. They can work in most salty ocean water. The light can be installed to boat hull surface by 3 M4 bolts. Input voltage range is 10-30V. Flood light model's emitting angle is 160° while beam light angle is 30°. Installed 30-50cm below water line. All models have built-in constant current driver.