Simple Set of Strainer Lid (Wide Mouth) and Container with Kefir grains. Set strongly simplify method for kefir preparation because exclude use of strainer and pouring from one jar to another. Container filled with kefir grains is functioning like one big solid very active grain. Lid with screen protect your fermentation and support aerobic conditions for grains. Removable screen has hundreds of tiny holes. Diameter - 0.7mm. Use any mason jar you have. Just place container with kefir grains inside jar and pour milk. Kefir will be ready in 20-24 hours. Type KEFIR FERMENTER to see other devices related to home kefir with or with out kefir grains