I check them several times a year; Tips fall into glasses cases. They probably cost a penny so I'm annoyed at how expensive they are, but how else can I get them? My optometrist gave them to me for free for a while, but I've had these frames for ten years, changed three sets of lenses, and they're not that nice anymore. i love frames I wear them to sports like basketball and they broke a couple of times, I just put the pieces back together, I think with these spares they will last forever.