Stern Defense AR-15 Mag Well Adapter for 9mm Glock, Black- MAG-AD9

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 G