1. Material:silicone 2. Sealed and leak-proof, recycled 3. Good scalability and strong elasticity 4. Temperature resistance -40 to 230 degree 5. Strong adsorption, freshness and no odor 6. One set contains 4 fresh-keeping covers of different sizes 7. Size: oversized 13.4x13.4 cm large 11.5x11.5 cm medium 8.6x8.6 cm small 6.1x6.1 cm 8. Weight: 56g