This replacement plastic ball is a factory original unit. This ball does not have a 4" diameter as it is closer to 3" in diameter.
If your existing system has a green ball, please find the green replacement ball by clicking here
Upgrade your First Flush system to the new Advanced Release Valve and you'll never have to repair the ball and seat system or replace the rubber disks again!
In freezing climates, all water should be drained from the first flush system and the inlet should be shut off to prevent additional water from entering the system. If preventive maintenance is not performed, damage to the first flush system, including ice crushing the plastic ball, may occur. The Advanced Release Valve eliminates the use of washers and allows for much greater control over the release rate of the first flush chamber.