E-Jen containers are light, simple, and very easy to use and operate unlike heavy crock jars. Perfect for any kind of pickling and fermenting from Kimchi to Sauerkraut. Also E-Jen containers can be used to store just about anything and everything that fits inside. E-Jen storage container comes with an adjustable pressing plate that acts as an inner vacuum. Fermentation allows food to retain more vitamins and minerals than other types of preserving. The pressing plate keeps the kimchi/pickles in an airtight space promoting an anaerobic state benefiting the growth of probiotics (lactobacillus). Anaerobic process; requires an oxygen-free environment. The design and shape of the containers make it easy to store goods in both the refrigerator and in the pantry without taking too much space. It contains and blocks smells and odours better than most containers due to the double lids and prevents smells/odour from lingering in kitchens or refrigerators. This product is food safe, dishwasher safe, freezer safe, microwave safe, heat and cold resistant. All materials are FDA approved and BPA, DEHP and lead free.