For use on boats up to 39.4\' (12 m) in length, provides 1-mile visibility. Twist/bayonet lock design secures lens and cover to base. Includes an 9-watt wedge base lamp and 7\" wire leads. Install with (2) #10 fasteners. Cover and lens conceal installation fasteners and seal out water. Visible 225°. Size: 2-3/8\" dia. x 1-7/16\" vertical height.