7.62x25 m-57 mags - Zastava Arms USA M57A 7.62x25 Rifle Magazine

Ordered three of these and they all functioned flawlessly. All other mags that I have including the one that came with the firearm gave me "FFE"s and "FFF"s". I had to tinker with them to get one or another to function reliably. Still trying to get some to work reliably. And these mags that I ordered from "OP" look to be of better quality. They all had positive seating and lock up when installed. Some of the magazine catch cut-outs in my other mags are so poorly positioned that some, I have to smack on the bottom to get them to lock in. A couple I can't get to lock in at all. No such problem with the mags I received from "OP".