Toto Flapper help

I replaced my fill valve in a Toto toilet so I decided to replace the flapper also which was about 10 years old, with a Korky 3" flapper, the one that has an adjustment feature. But the old white one, shown on top of the tank here, had a "fin" on the opposite side that held it open once you depressed the handle, since the fin functioned to keep the flapper open for a few seconds. . Now with the new one I have to hold the handle down to complete the flush. Does anyone recognize the brand of the old white flapper in the photo? Do I have to get this same model?

The Korky should work. It looks like you have too much slack in the chain. The chain should be no longer then needed for the flapper to seat on the flush valve.

John

Thanks. I had shortened the chain by moving the clip but did not cut off the links I bypassed. I just shortened it a little more and that helps since the flapper goes up at a higher angle when you flush and stays there an instant, so you don't have to keep the handle depressed. Then I had a momentary problem in that the valve kept running and hissing. Oh-then I saw the problem-that's why you cut off the excess chain, the end of the chain had gotten caught in the flapper, causing the flapper to not close all the way.