83690 IPS 4 in Flush Mechanical Cleanout Repair Plug The first cleanout repair plug the really works! Holds up to 50 feet of backpressure! Seals air tight! (Does not rely on threads to seal.) Back pressure actually increases sealing ability! Center is tapped for screw, and can be covered with cleanout cover Completely flush inside and out! Stainless Steel flast head screw! Cannot fall into the pipe! Comes with wrench! Patent 7,464,727