A Bosnian company, AC-Unity, is bringing a quad stack magazine for 7.62×39 AKs to the US market. The 60 round capacity magazine features polymer construction with a clear window running down the length of the magazine and metal reinforced front and rear locking tabs (no reinforcement in the feed lips). The follower design locks the bolt to the rear on empty and the manufacturer claims the magazine will be impact resistant.
The AC-UNity Quad Stack magazine weighs 12.35 ounces unloaded and around 3 pounds loaded (depending on the type of ammo) which is significantly less than a 75 round drum magazine. The retail price will be around $80.
Initial reports have indicated that there may be some length of break-in period for the magazine. At least one very early test indicated some follower binding that seemed to improve with use.
AC-Unity has a basic website that is still under construction. These are already available for pre-sale at a handful of retailers.