I just ordered 3 Euro. mags. from ATG and they will not fit into my Mak90. It came with a cheap polymer Pro-Mag when I bought it. No problems at all locking the Pro-Mag in and these are all 4 30 rounders. The tab on the back of the Pro-Mag doesn't look as thick as the Euro's. I really like this Mak90 and this is kind of upsetting. Any help would be appreciated. I tried the pre-ban Chinese mags also with no luck. I do see a little rivot in front of the mag release. It looks like it is being rubbed. This is kind of a headache and it is looking like I might have to file on the Ak.