Features:

  • Plastic
  • Imported
  • Replacement flapper: designed for use on a selection of TOTO 3 inch flush valve tanks
  • Replaces the following TOTO flapper part numbers: THU138S, THU175S, THU331S, THU140S, THU299S, THU253S, THU277S, THU347S, THU275S, THU332S, THU369S, and THU499S
  • 3 inch sealing surface
Easy installation! Follow the chart given for best fit.

Fit much better than the one my plumber replaced the last time. I admit I need to get with Toto company to follow the directions for a good fit. (My Toto toilet did NOT have the stamped serial inside the tank) There are specific notes on chain length and a dial to fit the opening. So after the representative told me which style to use from the chart on the replacement product; It was a 2 minute installation and my toilet flushes with ease.

Easy for a novice to install

I found this Toto OEM flapper after confirming with Toto that this was the current replacement for my THU499 flapper. If you have any question about compatibility, lift the lid on the tank and note the model number of the toilet. Call Toto customer service for them to tell you the correct flapper number. The THU500S comes with clear instructions for setting the plug, cutting the chain to the proper length, and affixing to the toilet. The only tool you need is a pair of pliers or wire cutters. The whole process took less than 10 minutes.

Toto THU500S Well-Designed Replacement Flapper

After renovating our home three years ago, we were disappointed that our brand new Toto toilets were leaking. It appears that the original flapper, which was THU331S was inferior in quality and design. Toto suggested that we replace it with THU499S, however when we purchased and installed that flapper, the toilet leaked the same day. After several months, we found out from another Amazon user that Toto informed him that THU500S replaced THU499S as its better design prevented many of the various toilet models from leaking. We installed the THU500S flapper two months ago and it is definitely performing well.

Looks like a better design for a toilet flapper

This flapper is slightly different from the ones you get from big box hardware stores, such as the common Korky brand types. This one has a rigid plastic black top with the soft rubber making up the red colored "ring" that does the sealing in the toilet. The other common one is totally made of rubber, and after being in the toilet for years with rather heavy usage (I work from home), it will become soft and the entire flapper goes out of shape and won't seal properly. Time will tell if this design with a rigid plastic top will work better but I have high hopes for it. Installation is easy if you know the model no. of your TOTO toilet. All you have to do is to dial in the correct no. on the flapper to suit your toilet and adjust the hook on the chain to the proper length. The instruction on the packaging shows you what is the correct length for your TOTO toilet but if you're using something else, simply adjust the length by putting in the flapper and holding the chain up to the flushing level rod.

Great Deal at $12.10 !

LIKE: Great deal when price drops to $12.10. I buy several and have found that the flappers will remain soft and flexible, despite being stored for over a year. DISLIKE: None. But here are tips: A bit complicated to understand, so once you do it successfully, write down the specifics (I write on the inside of the tank lid). When you remove the old flapper's two black, pinch, clips, from their pivot axle, be extremely careful not to break the axle. When installing the flapper, its easy for the white colored, circular, plug, in the hole at the bottom of the flapper to fall out, so keep it from dropping into the tank-to-toilet inlet. The flapper prevents leakage by being very flat and very soft. So, once it becomes dished/convex, or rigid, it must be replaced.

Solid and easy to install

Seems more solid and durable than the THU331S which began leaking after 3 years. Instructions had accurate settings for our Toto CST-874. A tip for replacing older models without clip-on arms: first use a snips to carefully remove both arms, then pliers to get a good grip on each remaining chunk of plastic and angle it under the peg. There's a detailed installation video on Toto's website. The seal is wider so I expect this to last many years.

Fits my 604 Ultramax Perfectly

Fits perfectly! I had replaced an old one with a Korky brand that said it was compatible with my Toto Ultramax. It wasn’t. It constantly leaked water into the bowl and the tank kept refilling every 15 mins or so. I noticed that the Korky one was able to move a good 1/4” laterally. I’m not sure if that was why it leaked but this Toto one fits a lot better. No more leaking! Feels more rigid as the body is half plastic, half silicone rubber. High quality materials. I’m going to get 2 more for my other toilets.

Super easy to install - DIY and save money

The THU500S fit's a nearly couple of dozen different 3" Toto flapper tanks, and it's super easy to install. Just get the model number of your tank (which should be inside of the tank lid, or within the tank that start with a CS... or ST... part number), adjust flange arrow setting, set the count and cut appropriate the links, then attach the hook to the appropriate hole on your toilet handle lever hole inside the tank. Whole process takes less than 10 minutes to swap out this flapper with one that is failing in an applicable Toto toilet tank. Calling a plumber to do this job is a complete waste of money, as anyone who can this, and you don't need special tools to do the job (other than a pair of scissors). Owners of a Toto toilet with a water tank should always keep one these spares in the closet just in case the factory original fails unexpectedly after several years of usage.

Easy to install and it works perfectly!

After doing a little research on the exact replacement flapper I needed for my Toto toilet, I found the right flapper quite easily on Amazon. I ordered the flapper on Monday, and received it on Wednesday. The flapper was packaged well, with no damage upon arrival. I removed my old flapper, and installed the new one in less than 2 minutes. Very easy. After 2 days, the flapper works perfectly with a tight seal and no leaking. I guess the most important thing is to make sure that this flapper part number is compatible with your toilet model. I plan on purchasing another today for my second toilet. I hope this helps.

THU500S is the newer, updated version of the THU499S.

Per TOTO comments on THU499S: "The THU500S is the newer, updated version of the THU499S. The THU500S has slightly different angles in order to combat some of the leaking issues that were occurring in a small selection of tanks." This flapper requires adjustment during installation per the included configuration guide. See attached images. The rigid black backing should prevent "dishing" of the older all-rubber designs as the flapper ages. Eventually this creates leaks.

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