Hi Victor, I really like the flip brand you use commercially. I like how the opening goes almost all the way to the fold, which allows access but seems more secure than flips whose opening only goes part way. Plus, the flip feels more pliable. What brand is it?
I forget the flip brand I have, but after about a year or so, they become so brittle that they almost always crack significantly at the fold. I just figured that was the "cost of doing business" and I regularly replace the flips of coins I look at a lot. It seems that somewhere I was told that the brittleness means certain chemicals aren't in the flip--chemicals that could damage the coin over time. In short, brittleness was a good thing. The soft, unbrittle flips were the ones that might damage coins.
Is this information correct? How do you, or anyone on this list, balance coin safety with flips that might have some longevity?