Thanks to intelligent engineering, Attwoods plug-in Marine Light Armor Base has a threaded design that perfectly matches up with the locking collar found on any of Attwoods light poles. This locking system ensures a strong, secure, rattle-free fit. Its low-profile cover protects the base and stays secure while the light pole is not in use. Available:Two-Pin Design, Three-Pin Design (not shown). Cancer and Reproductive Harm- www.P65Warnings.ca.gov. Type: Navigation Lighting.