You may want to try a flapper made of silicone rubber. I believe these are
a reddish pink color.

"Calab" wrote in message
news:6hBvk.245647$gc5.42449@pd7urf2no...
I'm getting very tired of constantly replacing the rubber flappers on our
three toilets. I've tried different suppliers and grades, but after a few
months they seem to distort and start leaking.

I know that there is no buildup on the flapper, or the hole where it
seats. The pull chain isn't snagging and holding up flapper. Why would I
get leaks after a few months?

Anyhow, I'm looking for an alternative for the flapper on my toilets.
Something that will last a good while before needing any kind of repairs.
Any idea on what I could use?