I was given a box of fairly ancient canning stuff...jars, rings, lids, and assorted gear.
In the box there were several new, unopened boxes of ball type pop up lids. They look great, and have no rust or obvious damage. But they're probably 20 years old...maybe 30.
You think they're ok to use? My concern is that all that time may have changed the properties of the seal material, which obviously could be a big problem.