USCG certified for two-mile visibility for sailboats and powerboats up to 65' (20 m). 12-volt. For direct side mounting. Polycarbonate housing that is shock resistant, non-corrosive and seawater resistant. Time-tested, patented design that has become the industry standard by which all other designs are compared. Dimensions: 3.6" width x 4.1" height x 3.2" depth. Includes 25 watt/12-volt bulb, replacement PN 90002-7.