There are two different versions of these mags. One is simply described as "steel lined" and sells for around $10 or thereabouts. The other one also has steel front and rear lugs and runs about $14. I've never had any of the cheaper versions. But I do have and have used the $14 versions and they seem to function as good as any AK mag I've ever used. In fact, I haven't bought a steel mag since discovering these, though I do still keep a bunch of old surplus steel mags in storage. These may not be as durable long term as a steel mag (or even the Circle 10 mags). But they are durable enough and run like a sewing machine, while being far less heavy and cumbersome than the steel mags. And the price is right, making them suitable for stockpiling in quantity. The Circle 10 magazines are certainly nice, but at $45 a pop, most folks aren't going to be buying many of those. So I'll just keep laying back the $14 Bulgy mags and if someday I manage to damage or break one, I'll just toss it aside and grab a replacement out of storage.