Tired of scupper leakage? Replace your old worn-out flapper scupper with this Flow-Max positive sealing ball scupper. Easy twist-off design makes cleaning debris a snap. Simply twist counterclockwise to remove ball cavity, clean out and twist back on. Stainless steel security pin provided for added safety. Larger exit hole allows 70% more water drainage than its nearest competitor. Multiple mounting holes make retrofits quick and easy - no filling holes or re-drilling. Neutral buoyancy ball insures ball won't float up and break seal. Meets all ABYC standards.