I left another forum over the flames I got on this subject, but here goes. If you get an "unmarked" factory 12 round USP magazine, it was stolen from the U.S. military-period. Hk never made unmarked full-size 12 round .45 mags, except for the Mk23's that were shipped to the military. Many of the spare mags have grown legs and I know for a fact that NIS and BATF have done investigations related to these thefts. So basically, you are taking a huge chance in dealing with these magazines. This is not some holier than thou attitude, or preaching, but I would hate to see some of my buddies get hung out to dry on a sting operation, or in trouble over these things. Many law enforcement firearms people are aware of this, and I know Hk is concerned about it, so it is a serious issue that is being looked at.