The Double Pistol Mag Pouch is designed to hold 2 Glock magaznies but will hold so much more. It includes 2 scrim flaps to hold various items if you desire a more certain retention. 
 
The rear features .5" MOLLE spacing to fint on blets and other non MOLLE spec 1" spacing, as well as anything with normal spacing. There is 2 included pieces of Velcro one wrap if youd like to run it on a belt and keep it in place.