Advanced Armament Corporation Flange Indexing Direct-Thread Adapter 5/8''-24. The AAC Direct-Thread Adapters are unobtrusive low-profile designs that feature a muzzle-brake structure that divert gas and unconsumed propellant away from the projectile aperture and protects the blast chamber baffle from premature erosion. AAC Flange Indexing Direct-Thread Adapters feature a tool-featured flange with a square shoulder that indexes against the rear face of a host suppressor. Flange Indexing Direct-Thread Adapters should be compatible with most suppressors with industry-standard 1-3/8-24 threaded sockets. Specifications for Advanced Armament Corporation 65011 Flange Indexing Direct-Thread Adapter 5/8"-24 T: Manufacturer: Advanced Armament Corporation Gun Make: Universal Length: 5.2 in Advanced Armament Corporation 65011 Flange Indexing Direct-Thread Adapter 5/8"-24