The lids will last a lifetime, and beyond quite honestly. They are BPA and Phthalate free, and made from a food grade plastic known as Acetal Copolymer, designed to withstand temperatures well beyond what you will find in a safe canning environment. Assuming you don’t exceed recommended temperatures in a pressure canner (240 degrees F), your Harvest Guard Reusable Canning Lids will outlast you!