Amazon has the MJSI HYR270 HydroRight Drop-in Dual Flush Converter for
$19 with free shipping on orders $25 or more. Otherwise shipping is $6. Converts your toilet into a water-saving two-button version with a quick flush for liquids and paper. Approximate savings of 15,000 gallons per year for a family of four. Easy installation, but will not fit all toilets, read product description for details.
ive had more then one plumber tell me that these dual flush kits can cause major problems as not enough water goes down with the minimum flush to move solids that are already in the line. thus, solids get trapped and can cause a clog and backup.
I have one and like the function, but would recommend against this "button" type as they are REALLY difficult to push - painful even.
There is a lever-type of these and they are much easier to use. Unfortunately, you cannot convert between the two.
These don't fit in tank which have a raised opening for the flapper. In these cases the tanks lid will rest on top of this contraption and not close. It may fit if the opening for the water is at the base of the tank.
My calculations show that with all four family members using the same 2 gallons/flush low flow toilet saving 50% with this gizmo would require 13.6986301369863 toilet uses per person per day. And half of those are number one the other half are number two.
^ Up to you, I'd rather not have a low flow toilet then have the option to do a limited flow flush. The question to me is how reliable and long lasting are these gadgets? I don't want a shorter replacement interval nor to wake up one morning and find out it leaked hundreds of gallons down the drain overnight.
like to hear a review from someone who has had one for a long time to see how well they really work