[Reliable material]-The fermentation lock is made of high-quality pp plastic, environmentally friendly, odorless and non-toxic, sturdy and durable, and can be used for a long time. The transparent air lock allows you to look inward so that you can watch the air lock do the hard work for you. You can use and buy it with confidence. [Single seal valves principle]-The brewing airlock adopts the principle of a single-sealed valve, which can effectively cut off the outside air of the fermentation medium to prevent oxidation and make fermentation easier. And allows the entire fermentation process to automatically ferment and discharge at room temperature without manual control. It effectively prevents flies from entering wine/beer with a cover included. [Easy operation]-Fill the wine airlock with water and insert it on the lid of the brewing bottle, or the rubber plug or silicone plug on the top of the fermentation container, and cover the small cap with hole on the airlock. Without manual control, simple and easy to use, operation, and also can long-term repeated use. [Convenient to clean]-The S-shape air lock is practically designed and easy to clean. The airlock can be disassembled. You only need to use a small brush to clean it thoroughly. You can soak it in bleach water for disinfection. It is more efficient and saves your energy and time. [Brew your favorite drink]-The airlock set for fermentation has many uses and is a good helper for fermented food, such as preserved food, cabbage, kimchi, sauerkraut, home brewed beer, white grapes, mead, red wine fermentation, etc. It can meet your daily fermentation needs and provide convenience for your life. Material: PP plastic Color: Transparent Size: 17.5*5.5cm/6.9*2.2inch Weight: 30g Packing includes:2*Fermentation airlocks