USCG certified for two-mile visibility for sailboats and powerboats over 65 ' (20 m) up to 164' (50 m). Deck Mount. Completely sealed design that is UV and saltwater resistant. Polycarbonate housing that is impact and shock-proof, non-corrosive, non-magnetic and seawater resistant. Bulb not included. Use 90002-7 (12V/25W), 90003-7 (24V/25W), 90285-1 (32V/25W), 90286-1 (120V AC/25W).