Unique support base for this type of toilet in Greece, so we don't have many options. For the specific toilet that I needed it for, it was wide, so I needed to use two flanges, one on top of the other, to seal the toilet tank. But it worked (for one month now, everything is fine) and it saved me the set (toilet-tank) that would cost around 200+ euros without liking the options. I found it much cheaper on English websites and with a greater variety, but the shipping costs, combined with the delay in delivery, prevented me from further dealing with it.