Kefir fermenter: Container for Water Kefir Grains & Milk Kefir Grains - transformable Milk Kefir or Water Kefir can be made with this container. Just transform Universal Container for milk fermentation (4mm holes) or water kefir fermentation (1mm holes). For Milk Kefir: remove polyethylene mesh with 1mm holes from container and place Kefir Grains inside. Access of milk to kefir grains is reliable through 4mm holes. For Water Kefir: install polyethylene mesh and add water kefir grains. Holes of mesh 1 mm : liquid freely goes inside but small grains are not lost. Inner volume is 55 cubic centimeters = 1.5 big table spoon. It is enough for fermenting 0.5 - 1.0L of homemade healthy soda or milk. You can buy it together with glass Fermenter (1.0L) having two lids (with micro-holes and solid): typeB01DLEZ0HO. See instruction in images.