Forward Controls Design Flash Hider .30 Carbine 5/8x24 Nitride Black. 9" barrels compatible with .223 Dead Air sound suppressors with Keymo interface. 6310KM-L is 2.7in long and can bring a 13.9" barrel to non-NFA length (16.1in assuming 0.5in of threading on the barrel) Threaded for 5/8 x 24 precision machined from solid 4140 steel bar stock heat treated and QPQ coated it is probably the finest A2 style comp/flash suppressor ever produced. Its 3 and 9 o'clock ports are 25percent smaller (shorter and narrower) than the other three upward facing ports so more gas is vented through the upward facing ports it is a superior compensator to the A2 its flash suppression is equal to that of an A2. 6310KM-L is compatible with Dead Air 30 cal sound suppressors. 6310KM-L is a light blended performance muzzle device. It provides 15percent to 20percent better muzzle rise compensation than the A2 and what is impressive is that it does so without sacrificing its flash suppression capabilities or creating more noise and concussion. Forward Controls Design is an authorized licensee of Dead Air suppressor mounts. Do not use a crush washer if this is going to be a suppressor host. Specifications for Forward Controls Design 6310KM-L Flash Hider: Manufacturer: Forward Controls Design Color: Black Caliber: .30 Carbine Finish: Nitride Fabric/Material: 4140 Steel Threads per Inch: 5/8x24 Length: 2.7 in Weight: 3.42 oz Barrel Length: 13.9 in Package Contents: Forward Controls Design 6310KM-L Flash Hider Single use packet of Rocksett Forward Controls Design 6310KM-L: 6310KM-L Flash Hider .30 Carbine 5/8x24 Nitride Black