Before beginning the installation of your One2flush valve; read instructions completely and check that your tank specifications match with the One2flush system.
Most front, left and right side, handle mounted tanks are easily adapted with the One2flush kit.

Basic tank configuration - almost every tank from 1.6 gallons to 7 gallons with a 2" - 2 1/2" tank-to-bowl hole are easily adapted.

Note: If your toilet tank has not been removed in the past ten years it may be necessary to replace the tank seal and hold down bolts when installing the new valve.