Silver metal plastisol lined jar caps with buttons are available in the 70G (70/450) neck finish size that is easily paired with a range of glass jars for canning. The silver jar caps include plastisol liners that are activated through various canning processes. When the seal is created, the center button will depress, and once the jars are opened, the button on the jar caps will pup up, alerting that the tamper evident seal has been broken. Be sure to test these silver jar caps with your products and canning process to ensure complete compatibility.