Review on Fluidmaster 400AKRP10 400AKR Universal Install by John Stefko

Not suitable for Gerber or Kohler toilets if you replace the flush valve (the one with the damper). Gerber and Kohler have more space between the tank and shell. This kit will flow like crazy. But everything is fine with the filling valve. The problem is in the feed. What to do!? I bought a Fluidmaster K 507A 008 at a local store for $15. It comes with a seal for Gerber and Kohler toilets. It also has an adjustable overflow pipe which is way better than the one in this kit. Installed today and no leaks. Save your old gear as you can reuse it. I replaced the rubber washers and bolts but used the old plastic nuts. Revain has a Gerber kit that includes hardware, but it costs $15 and unfortunately doesn't include a flush valve. Find out what works best for you, but be prepared to pay around $30 when you're done. I have a Gerber 21-762 which I believe was made in the 90's.