A high percentage of the ones I have installed on customers' toilet either start leaking right away or they leak within a month or so.The original blue Power Gravity or the red GMax flappers work well for me when I install them. On the last job I installed a FluidMaster 3 in universal and that one worked, at least for now.

I expected the THU500S to work because it seems to be supplied by Korky, with the red seal made of their Chlorazone rubber.The Korky 2023 looks identical. I don't understand why they leak. Surpringly, it gets good reviews on Amazon.





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I have been using the Korky 3060BP for a while with good results for 3" flush valves.....

I have a few Korky 3060 but have been hesitant to use them because of the odd mounting clips on them. I expect them to slide off the flush tube ears when they are lifted up for a flush.

I am going to try them out, considering you have good results with them.

I have used a lot of them for a few years and have not had any of them slip off the post. They snap on pretty good.

What scares me (besides my wife) is trying to remove an old flapper that has molded in holes that become hard as a rock and trying to get them off the ears of the flush valve without breaking them. I have not broken any of the ears yet. Fingers crossed.

If possible I try to cut the flappers off. Not always enough room to do this.

I too try to slice open the ears of the flappers if they do not come off easily.

Couple of years ago I managed to break off one of the two posts on the flush tube of an American Standard 2 pce toilet. A post mortem revealed that the flush tube had been installed with one post almost against the back of the tank and I had tried to squeeze the flapper ear through an inadeqate gap. Since then I am extra careful with the posts.