FightLite Mission Configurable Rifle AR-15/M16 5.56x45mm NATO 12.5 inch Upper Receiver Assembly 1/2x28 Threads Manganese Phosphate Finish Black. Once installed the patented MCR upper receiver system can be user-configured in seconds without tools to adapt to virtually any mission profile. Specifically designed for responsible armed citizens law enforcement and professional security personnel who wish to upgrade their rifle or carbine to MCR performance and capability; standard features include gas-piston operation for extreme reliability in adverse conditions; a 16.25" quick-change (3 seconds) barrel system and a MIL-STD 1913 co-planar hand-guard with rail-interface system for the mounting of optics and modern accessories. Specifications for FightLite Mission Configurable Rifle AR-15/M16 5.56x45mm NATO 12.5 inch Upper Receiver Assembly: Manufacturer: FightLite Caliber: 5.56x45mm NATO Barrel Length: 12.5 in Finish: Manganese Phosphate Black Color: Black Gun Rail: M-LOK Gun Make: AR Platform Gun Model: AR-15 Additional Features: Threaded Upper Handle Color: Black Features of FightLite Mission Configurable Rifle: Accepts ALL AR15/M16 Magazines & M27 Linked Ammunition Package Contents: FightLite Mission Configurable Rifle What firearm models does the manufacturer say FightLite Mission Configurable Rifle AR-15/M16 5.56x45mm NATO 12.5 inch Upper Receiver Assembly is compatible with? The manufacturer says that FightLite Mission Configurable Rifle AR-15/M16 5.56x45mm NATO 12.5 inch Upper Receiver Assembly is compatible with AR-15FightLite MCR-060MS: Mission Configurable Rifle AR-15/M16 5.56x45mm NATO 12.5 inch Upper Receiver Assembly 1/2x28 Threads Manganese Phosphate Finish Black