3 LitersGlass Demijohn. 2 x3 LitersGlass Demijohn. with 2 x Airlock Bubblers Bung. 2 x Bubbler Airlock. High Quality Bubbler Airlock for Wine and Beer Making. It is essentially a one way valve. with 9 mm Hole for standard airlock, bubbler, stopper -33x29mm.
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