I have several 10rd PMAGs Gen3 that I have coupled at their base, to form a regular sized magazine. So Spartan's PMAG hanger will not work for me due to there not being a standard base to hang from. I figured that the Metal Mag holder would work and it does. It is a perfect fit. I will be ordering more for the rest of my coupled PMAGs. My safe is already beginning to look cleaner.