This Thru-Hull with Scupper Valve mounts through the transom and provides a water exit for boats with self-bailing cockpits. Ideal for above the water line drainage. Valve features a soft black flapper. For use with 1-1/2" hose. Compatible with most self-bailing applications. Constructed of injection molded acetal. Installs with four #6 FH fasteners (not included).