I have 3 toilets in my house, and in 5 years, 3 HS mechanisms were because of this damn valve that had holes or ITHDRAWAL downright torn!
My mechanisms come from Leroy, Casto, Brico Depot or Bricoman ... these are all models compatible with this valve!
Except that store, I have found ... THAT Leroy to 5.70 euros versus 7.44 VALVE ... 2 ... go here !!!
No leakage, same product, same size ... dismounted / remounted 2 mins ... very very happy with my purchase (which saves me from having to buy a complete mechanism 15 or 20 euros for a slotted rubber piece :)) ... my 2 or 3 alternative mechanisms sleeping in the garage because the valve was punctured have found a new youth :)