Threaded for 5/8x24, precision machined from solid 4140 bar stock, heat treated, and black nitrided, it is probably the finest A2 style comp/flash suppressor ever produced. Its 3 and 9 o'clock ports are 25% 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. 6315 is compatible with M16 BFA and most A2 mounted sound suppressors. Note that since 6315 does have flash suppression capability equal to that of an A2, it is to be treated as a flash suppressor for states that feel threatened by them, such as CA, MA Mfg: Forward Controls Design