Reliable material: These airlocks are made of PP plastic, which is odorless and non-toxic. The airlock grommets are made of silicone, durable and soft, safe for your use, suitable for long-term use. Keep good seal: Easy to use. Just drill a suitable hole in your fermenter lid (follow the size of the air valve), then insert the black grommet into the lid hole. Place the tapered tip of the airlock into the grommet hole to create a good seal. Convenient to clean: Designed for easy cleaning. The airlock can be disassembled. Use a small brush to clean thoroughly, and it can be soaked in bleach water for disinfection. Main function: This airlock kit is versatile fermenting equipment, suitable for a variety of purposes such as food preservation, fermenting cabbage, sauerkraut, grape juice, and for making beer, wine, mead. Specifications: Material: Plastic, rubber Colors: White, Black Package includes: 20 x Silicone grommets 6 x Plastic airlocks Only the above package content is included; other products are not included. Note: Light and different displays may cause the color of the item in the picture to be slightly different from the real thing. Measurement allowed error is +/- 1-3 cm.