The MK116 MOD 2-M Upper operates on the highly acclaimed PWS Long Stroke Piston System, renowned for its reliability and reduced fouling. The inclusion of a 3-setting Adjustable Gas System allows users to fine-tune gas flow, ensuring optimal performance in diverse shooting conditions as well as optimizing it for suppressor use. This innovative system not only enhances reliability but also provides adaptability to various ammunition types and environmental factors. Specifications for Primary Weapons Systems MK116 MOD 2-M, .223, 16in Upper Receiver: Manufacturer: Primary Weapons Systems Caliber: .223 Wylde Barrel Length: 16 in Gas System Length: Mid Length Barrel Twist Rate: 1-8 Threads per Inch: 5/8x24 Muzzle Device: FSC 556 Finish: Matte Color: Black Fabric/Material: 41V50 Chrome Moly Vanadium Steel Gas Block Journal Size-Diameter: .750 in Handguard Length: 15 in Additional Features: 3-Setting Adjustable Gas System Condition: New Bolt Carrier Group Included: MIL-SPEC Magazine Included: No Features of Primary Weapons Systems MK116 MOD 2-M, .223, 16in Upper Receiver: PWS Long Stroke Piston System: Renowned for reliability and reduced fouling, with adjustable gas settings for optimal performance. Suppressor Optimized: Provides enhanced suppressor performance by minimizing back pressure, reducing gas blowback, and optimizing gas flow for a cleaner and more comfortable shooting experience. .223 Wylde Chambering: Meticulously designed for outstanding accuracy and reliability, accommodating both .223 Remington and 5.56mm NATO. Lightweight Design: The MK116 upper weighs just 4.6 lbs, ensuring superior maneuverability without compromising performance. Barrel: 16.1" .223 Wylde barrel with a 1:8 twist rate, delivering exceptional accuracy and versatility when firing both .223 Remington and 5.56mm NATO rounds. PWS FRC 2-Port Compensator: A suppresor compatible compensator that expertly mitigates recoil, muzzle rise and is compatible with the Rearden Atlas suppressor mounting system. Innovative PicLok Handguard: Combining both Picatinny and MLOK into one for mounting accessories, balancing ergonomics and functionality. Radian Raptor Ambidextrous Charging Handle: Ensures smooth operation for both left and right-handed shooters. Package Contents: Primary Weapons Systems MK116 MOD 2-M, .223, 16in Upper Receiver