The sleeves appear to be pretty good in thickness and durability. I had a few that were not separated from each other, which usually meant that one of them was not usable after I tried to separate them from each other. The biggest issue is that they are significantly larger than the cards I was trying to sleeve in them. I bought a bunch of other sleeves from another company (that only sells in bulk) but I needed a few more than what I had. So I bought this to sleeve the remaining cards. The sleeves are a few millimeters wider than the others (which were a tight fit) and also several millimeters taller, as well. The combination makes it hard for them to fit into my card box that is designed for sleeved cards.Overall, not really impressed, but they will do the job and probably last longer than the other bulk sleeves.