TacFire AR Build Kit Features The TacFire AR Build Kit centers on a USA made 4.5 inch 9mm barrel paired with a matching 9mm bolt carrier group giving the builder a correctly sized action for reliable blowback cycling in a pistol-caliber platform. A Mil-Spec upper receiver also manufactured in the USA houses the barrel and bolt carrier group while a slim free float 4 inch M-LOK handguard keeps the forend lightweight and ready for accessories. The kit s 1/2x36 threaded flash forwarder allows for muzzle devices to be added to the 9mm barrel. A dust cover and forward assist complete the upper rounding out the core action components needed for assembly. On the lower side the included complete lower parts kit built in the USA supplies the fire control group pins springs and detents needed to finish the receiver paired here with a Black A2 pistol grip and a thumb safety. A Mil-Spec pistol buffer tube with a foam cover heavy buffer and buffer spring are matched specifically for pistol-caliber AR applications along with a Mil-Spec charging handle for manual cycling. A standard receiver end plate and a Mil-Spec and commercial castle nut secure the buffer tube to the receiver. This build kit gives AR enthusiasts nearly everything needed to assemble a 9mm pistol-caliber platform in one coordinated package. TacFire AR Build Kit Specifications Manufacturer: TacFire Model: AR Build Kit Caliber: 9mm Barrel Length: 4.5 Color: Black Action: Semi-Auto Firearm Type: AR Platform Grip Type: Black A2 Pistol Grip Safety: Thumb Stock Description: Buffer Tube Available At: GrabAGun