After reading the previously reviewed Wild Fermentation, I ended up getting this Polish-made crock pot. It has a lip you fill with water to keep unfriendly bacteria out. Note: If you want weight (recommended), get the 20-liter stone weights, not the smaller ones. Anyway, sauerkraut (great for digestion) is composed of: cabbage and salt, nada mas. Simple! First batch worked great. Centuries-old low tech.