Primary Weapons Systems FRC Flat 2-Port Compensator Features The Primary Weapons Systems FRC Flat 2-Port Compensator is a square shoulder muzzle compensator threaded at 1/2x28 engineered for barrels with a square shoulder profile and purpose-built to serve as a suppressor host for the Rearden Atlas and Atlas XL mounting systems across the broadest caliber range from .22 to .375. The 2-port design redirects muzzle flash away from optics and the shooter s line of sight maintaining a clear unobstructed sight picture during rapid fire while minimizing the distracting overpressure that affects conventional muzzle devices on compatible rifle and carbine platforms. When paired with a compatible Rearden Atlas or Atlas XL suppressor the FRC Flat 2-Port Compensator delivers a tight lockup that holds through hard shooting cycles without loosening or shifting under sustained fire. The 1/2x28 square shoulder 2-port compensator and suppressor host covers calibers from .22 to .375 extending compatibility to pistol-caliber carbines and smaller bore rifle platforms running square shoulder barrel profiles at the most common thread pitch. At just 1.64 overall it adds minimal protrusion beyond the muzzle while delivering full Atlas and Atlas XL suppressor mounting functionality in the most compact form factor in the FRC Flat lineup. The 1/2x28 configuration complements the 5/8x24 version giving shooters a matched FRC Flat 2-Port Compensator option across the two most common rifle and carbine thread pitches in the Rearden Atlas ecosystem. Primary Weapons Systems FRC Flat 2-Port Compensator Specifications Manufacturer: Primary Weapons Systems Model: FRC Flat 2-Port Compensator Caliber: .22 to .375 Thread Pitch: 1/2x28 Shoulder: Square Type: 2-Port Compensator Length: 1.64 Mount Compatibility: Rearden Atlas Rearden Atlas XL