Bought these for my dad because wallet windows don't last long. He liked this one (more than the others) because it had hard, clear plastic on both sides, so you could slide it into your wallet from the right or left, and it's sort of a buffer for the soft plastic windows that follow it. I'm sure they're just as flimsy as other windows (can't answer that question since they're new), but they're inexpensive enough to keep a few windows handy.
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