I do lots of maintenance work which includes changing ball valves in toilet cisterns, most push button cisterns are fine as I use the Fluidmaster with a brass shank.
The Hydroflow ( Torbeck type ) fits some cisterns with a normal syphon and handle but there no longer seems to be much choice if using a normal bottom entry plastic ball valve ( float operated valve )
Most plumbing merchants seem to stock the very cheap Opella type, see image.
What do you use?

The Hydroflow ( Torbeck type ) fits some cisterns with a normal syphon and handle but there no longer seems to be much choice if using a normal bottom entry plastic ball valve ( float operated valve )
Most plumbing merchants seem to stock the very cheap Opella type, see image.
What do you use?
