Viceroy Reliable Seal Canning Jar Seals, Fits Clamp-Down Regular Mouth Jars, Pure Natural Rubber Rings, Red, with Tab, 12 Rings per Box (Pack of 1) Fits regular mouth ball and other wire clamp jars. Inner diameter of 2.5" - outer diameter of 2.75" Made from pure natural rubber Includes tab for easily breaking seal 12 Count Red Rings