Rubber bung with hole to be used with Glass DemiJohns. Also fits our fermentation carboy. The size of our bungs are 27mm base diameter x 31mm top diameter, and they are 32mm high. Drilled with an 8mm hole to take our airlocks. All measurements approximate. Care should be taken never to stopper a DemiJohn that may have pressure build inside the vessel. If you are new to brewing then view our "How to Brew Beer guide" by clicking HERE |