Year of Plenty is proud to offer a beginner's Fermentation Kit. This set includes 4 fermentation weights and 4 fermentation lids - just what you need to begin making healthy, probiotic-filled fermented foods. You can begin making your first batch of sauerkraut within minutes of opening the package. The Fermentation Lids screw on to any wide mouth mason jar, creating an air-tight seal that allows gas bubbles to escape while preventing oxygen from ruining your ferments. The Fermentation Weights keep the ferments submerged safely below the brine. The weights fit ALL wide mouth mason jars (pint-sized, quart-sized, 1/2 gallon, etc). Preserve your harvest in a healthy and safe manner with this Year of Plenty Fermentation Kit.