The Carb Stone is designed for the the Blichmann Fermenator G4
This is a special order item and will ship directly from the manufacturer.
For the Blichmann Fermenatorª an optional tri-clamp blow-off offers an added safety net for agressive fermentations. After high krausen the hose and elbow can be removed and an airlock and provided stopper installed in its place. An optional tri-clamp blow-off offers an added safety net for agressive fermentations. After high krausen the hose and elbow can be removed and an airlock and provided stopper installed in its place. - See more at: http://www.blichmannengineering.com/tri-clamp-blow-kit#sthash.1WsiG3qU.dpuf