Grid Defense Complete Upper Receiver 5.56mm 7.5 inch Pistol Length 4150 M4 Barrel 1-7 Twist 9 inch Octagon M-LOK Rail Dimpled Flash Can Black. 56 Upper Receiver. Grid Defense constructed these Mil-Spec AR15 Upper Receivers from 7075 T6 aluminum for...
Grid Defense Complete Upper Receiver 5.56mm 7.5 inch Pistol Length 4150 M4 Barrel 1-7 Twist 9 inch Octagon M-LOK Rail Dimpled Flash Can Black. 56 Upper Receiver. Grid Defense constructed these Mil-Spec AR15 Upper Receivers from 7075 T6 aluminum for...