This twin bulb fixture can be used as a masthead light or an all-around light. Perkos Fixed Mount Combination light can be used as a 20pt white masthead or a 32pt white all around on sailboats and powerboats less than 20m in length. Designed to universally fit existing stern light installations, these lights are easy to install while looking great on your vessel. Key Features Visibility up to 3 nautical miles Fixed mount design features polymer base and a chrome plated zinc alloy top 3/4" dia. anodized aluminum tube For more information including mounting instructions, please refer to the Perko installation manual.