Silicone Material: The canning sealing rings are made from durable and soft silicone, which is leakproof, heat resistant, has great airtight sealing, and can be reusable. Leak-Proof Design: The mason jar rings are designed to create an airtight seal, preventing moisture or leakage, and maintaining the freshness and quality of the contents inside the jar. Easy Application: To use, simply place the silicone seal on the mouth of the jar and secure the lid, ensuring the seal is properly aligned to create a tight seal. Versatile Use: Great for canning, storage, and food preservation, these seals are suitable for preserving fruits, vegetables, jams, and other foods that require an airtight seal for long-term storage. Color: Green Material: Silicone Total Size: 10 x 9.2 cm/4 x 3.6 inch (L*W) Inner Diameter: 73mm/3 inch 4 Pcs x Silicone Gaskets Seals