Essential for fermented foods and fermentation experiments: "Airlocks." Please purchase if you understand how to use them based on the photos. ● New airlock bodies (with lids) x 4 ※ Retail price: Approximately 2,000 yen ● Used airlock body + silicone rubber stopper x 3 ※ Silicone rubber stopper: Top diameter 25mm, Bottom diameter 16mm ● Two-hole silicone rubber stopper x 5 ※ Top diameter 27mm, Bottom diameter 12mm This is a set sale. The two-hole silicone rubber stoppers do not have holes through them, so they can be used for things like pet bottle caps. The holes are small, so they cannot be used with an airlock without modification. Thank you very much for looking.