The wife and I got married in 1953. We got a mirro 4 Qt as a wedding gift. Use the cooker at least once a week. The lid gasget, jiggler, blow out plug are all in good shape. On thing we have always done is to wipe a little olive oil on the gasget. I think this little lubrication is the reason the gaget has lasted so long. Great old  pot--- I have a whole chcken jiggling away right now. Mmmmm.