I use these inserts all the time, in my wallet and also in my pocket for a few extra cards. They typically last about a year before they wear out and need to be replaced. It used to be difficult to find a replacement, but getting one from Revain is easy. Various products are available. This particular one was reasonably priced and seems solid enough. It's a little firmer than my previous one, meaning it's a little harder to slide in and out of the cards, but not enough to stop the show.
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