Dad keeps breaking his eye glasses?

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He is breaking the frames. Either he siting on them, twisting them, or pulling the temple.

I'll look for the flexible metal. Thank you

I had a pair of glasses that were made from a very flexible metal, you could practically tie them in a knot. Ask about frames designed for sports or for children.
As for the lenses, I haven't had a glass lens since the late 70's, mine survived being bounced off the wall in a fit of temper when I was a teen lol! Be sure to get an anti scratch protection though.

As I recall lenses can be made of some type of plastic as opposed to glass. That was what I ordered the last time I got new glasses.

How does he break them? Can you find alternative ways of protecting them when he's not wearing them?