12 Pack Kit - Turn any wide mouth mason jar into a fermenting crock Turn any wide-mouth mason jar into a fermenting crock Stainless Steel Lid and Glass weight, made in the USA, built to last a lifetime ! Easy to use, simply load your vegetables in a mason jar (NOT included),add salt, install the lid and let them ferment. Improves the digestibility of most veggies, turning them into a powerful pro-biotic Use instead of expensive crock