Replace flimsy and rust-prone screw bands with Tough Bands. Made of durable and food-safe plastic, Tough Bands won't rust and can be washed in the dishwasher. They're compatible with regular disc lids and create a secure seal. The unique faceted design is easy to screw on and off, making it perfect for food storage and fermenting. Perfect for storing food, liquids and fermenting. Creates a leak-proof and airtight seal. Designed for Regular Mouth Canning Jars (Ball, Kerr, Bernardin, etc.).