Polk Audio DB501 5-Inch Coaxial Speakers (Pair, Black) Pair of marine certified speakers perfect for use in boats of all types Equipped with a 0.75-inch liquid-cooled silk-polymer composite dome tweeter Maximum input power: 135 watts Equipped with a dynamic balance polymer/mica composite mineral-filled cone for a big sound Durable butyl rubber surround stands up to the stress of extreme temperatures, sunlight and time