For use on power driven vessels under 20 meters (65.6 ft.) in length. Perkos Economy White All-Round Pole Light provides 2-miles of visibility. It features a black plastic top, chrome plated zinc alloy base 3/4" diameter anodized tube with locking collar, and gold plated contacts. A 12V bulb is included with purchase and the light can be easily installed using size 8 screws. The base of each light measures 3-3/4" x 1-5/8" and certain models have telescoping capabilities.