Duotight BlowTie 2 Diaphragm Spunding Valve - 0-15 PSI Pressure FermentationThe Duotight BlowTie 2 is the most precise spunding valve on the market for pressure fermentation. Unlike spring loaded valves that fluctuate, the BlowTie 2 uses a large diaphragm to maintain a rock steady internal pressure in your fermenter. This allows you to carbonate your beer during fermentation, reduce ester production, and perform oxygen free transfers. Includes an integrated 0 15 PSI gauge and Duotight 8mm push fit connections. Fermentation