These are brand new in box we can ship directly to you please call or email for more information 
easily convert your standard AR-15 lower to use a pistol caliber glock mag !!!!!! 

Convert your standard mil spec AR 15, M4, M16 lower assembly to use 9mm and .40 S&W Glock Magazines! The Mag-AD series adapters install in seconds. Boasting a last round hold open feature making them a breakthrough product and a must-have for law enforcement and civilian gun enthusiasts alike. The Stern Mag-AD9 series adapters are made of aircraft grade aluminum, lightweight with ergonomic design.

Note: These adapters require the use of a 9mm or 40S&W barrel, "depending on chosen caliber" and a Glock cut bolt.