KAK Industry Plan B AK74 Muzzle Device M26X1.5 LH Thread Pitch 7.62X39MM Plan B Compatible Nitride Finish Black. These Plan B muzzle devices are compatible with Plan B suppressor hubs. It is recommended to use Rocksett for installation and 20-25 ft-lbs of torque. Some suppressor manufacturers will not honor warranty claims if other brands of muzzle devices are used with their suppressors. Specifications for KAK Industry Plan B AK74 Muzzle Device M2: Manufacturer: KAK Industry Color: Black Caliber: 7.62x39mm Finish: Nitride Black Additional Features: Brake Case Finish: Nitride Handle Color: Black Blade Finish: Nitride Features of KAK Industry Plan B AK74 Muzzle Device M2: Overall Length- 2.55" Protrusion into Blast Chamber- 1.55"" Package Contents: KAK Industry Plan B AK74 Muzzle Device M2