Made with a rugged 316 stainless steel cover for outstanding resistance to impact and corrosion. For use on boats up to 65.6 ft. (20 meters). A single external stainless steel lock screw attaches cover to base. Stainless steel electrical contacts. Cover design and integral gasket seal out water; make installation and maintenance simple. Includes efficient, high-output 10-watt bayonet lamp. Compact size allows installation on confined decks.