It releases carbon dioxide and is suitable for use in the fermentation of wine, dairy alcohol, and other beverages, helping to prevent oxidation. [Good Airtightness] The fermentation airlock provides excellent airtight sealing, facilitating efficient fermentation by effectively isolating external air and preventing oxidation. Automatically vents gas at room temperature without requiring manual control. [Easy to Install and Use] This dust cap features a textured surface for a secure grip and resists slipping during handling. Equipped with three internal buckles, simply press down gently to secure it in place; remove by pulling up and twisting. The lid does not require drilling, as a built-in gap allows gas to escape safely. [Reusable and Versatile] These airlocks are durable and reusable, designed for long-term use. Clean with disinfectant between uses for repeated application. Ideal for various fermentation projects including beer, wine, sauerkraut, cider, fruit wine, rice wine, vegetables such as broccoli, carrots, ginger, kombucha, mead, and home brewing. Suitable for primary and secondary fermentation processes such as white grape fermentation, red wine aging, and similar applications. Color: Transparent + Red + Black Material: PP Size: 17cm Package Contents: 6 x Airlocks, 12 x Sealing Rings (Only the listed items included; others not included). Note: Lighting effects and display settings may cause slight variations in color appearance. Measurement tolerance: +/- 1-3cm.