If you bought a 3″ TC dome lid for your standard Chronical this covers up that large 3″ tri clamp opening. 1/2″ tubing or an airlock and 2 stopper fit nicely in the 17mm hole. This cap comes standard with Brewmaster Chronicals and only fits on a 3″ tri clamp flange. Comes with a 1/2″ hose barb and pressure relief valve. 3″ tri clamp gasket and clamp not included.








