“Hydrometer” has been added to your basket. View basket Rubber Bung 1G (Bored) £1.50 170 in stock Rubber Bung 1G (Bored) quantity Add to basket Summary Specs Description Rubber bung with hole to take airlock. Suitable for use with demi john. Related products AccessoriesPotassium Sorbate 25G (Fermentation Stopper) £2.75 13 in stockAdd to basket AccessoriesNylon Bottle Brush £4.70 10 in stockAdd to basket AccessoriesVWP Cleanser 100Grm £2.65 27 in stockAdd to basket