ABC RIFLE COMPANY AR-15 .223 Remington/5.56x45mm NATO Rifle 16in Barrel Custom 15in Top Cut Hybrid M-LOK Handguard Complete Upper Receiver w/BCG And. The 16in 4150 CMV barrel with a 1:8 twist and A2 birdcage flash hider delivers consistent accuracy and dependable ballistics. A steel barrel nut .750 gas block and 9in stainless carbine gas tube provide smooth cycling under pressure. Finished with an MPI-tested nitride BCG forged milspec charging handle forward assist and ejection port coverthis upper is ready to perform at distance or up close. Specifications for ABC RIFLE COMPANY AR-15 .223 Remington/5.56x45mm NATO Rifle 16in Barrel Custom 15in Top Cut Hybrid M-LOK Handguard Complete Upper Receiver w/BCG And Charging Handle: Manufacturer: ABC RIFLE COMPANY Caliber: .223 Remington 5.56mm 5.56x45mm NATO Barrel Length: 7.5 in Barrel Twist Rate: 1-7 Threads per Inch: 1/2x28 Muzzle Device: A2 Flash Hider Finish: Cerakote Color: Black Handguard Length: 7 in Gun Rail: M-LOK Gun Type: Rifle Gun Make: AR Platform Gun Model: AR-15 Gas Block Journal Size-Length: .750 in Bolt Carrier Group Included: MIL-SPEC Charging Handle Included: MIL-SPEC Package Contents: ABC RIFLE COMPANY AR-15 .223 Remington/5.56x45mm NATO Rifle 16in Barrel Custom 15in Top Cut Hybrid M-LOK Handguard Complete Upper Receiver w/BCG And Charging Handle What firearm models does the manufacturer say ABC RIFLE COMPANY AR-15 .223 Remington/5.56x45mm NATO Rifle 16in Barrel Custom 15in Top Cut Hybrid M-LOK Handguard Complete Upper Receiver w/BCG And Charging Handle is compatible with? The manufacturer suggests that ABC RIFLE COMPANY AR-15 .223 Remington/5.56x45mm NATO Rifle 16in Barrel Custom 15in Top Cut Hybrid M-LOK Handguard Complete Upper Receiver w/BCG And Charging Handle is compatible with AR-15ABC RIFLE COMPANY UA15-BR16-TCABC15: AR-15 .223 Remington/5.56x45mm NATO Rifle 16in Barrel Custom 15in Top Cut Hybrid M-LOK Handguard Complete Upper Receiver w/BCG And Charging Handle Black