they will not rust.Durable for Use: Incredibly durable giving you that ability to keep reusing them without having to forgo any of the high quality.Perfect Color:they are perfect for that modern look that you want in your pantry.Tightly Sealed: These lids are the ultimate tight and fully protective covers. They come with silicon seal making your Mason Jar is tightly sealed.Multi-purpose: Perfect for storing fruits, jams, cookies or colorful candies, storing soft drinks, tea or coffee, or storing nails, screws and other small objects.for standard wide mouth mason jars.The metal lids are more durable than plastic and do not stain.Ergonomic contours make the screw top lids easy to open and close.With silicone sealing gasket would seal the jar properly, no leakage problem.They are not for canning. These lids are for freezer, dry storage.colour:SilverMaterial:Stainless steel + siliconesize:Diameter: 86mmPackage Contents:8x Mason Jar LidsOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.