Riflespeed Gas Control .750in Assembly Block RS7521 AR15/AR10. Need more gas? Turn it up. Need less gas? Turn it down. With the easy-to-grasp Control Knob it's that simple and no tools are required. The highly visible numbering on the Control Knob ensures that you'll always know your setting. Return to a previous setting instantly by simply turning the Control Knob. Each setting is indicated by a highly tactile "click" for use during times of reduced visibility. The modular design with multiple Plunger sizes cover the adjustment requirements for every available cartridge. The patented Rotation Stop feature prevents unintentional disassembly. Gas Controls require the use of RIFLESPEED or other straight gas tubes Designed for the most rigorous Military or LE Duty Use RIFLESPEED Gas Controls are also ideal for defensive use competition recreational shooting or hunting. RIFLESPEED Gas Controls are durable and proven to perform through tens of thousands of rounds of ammunition spent in developmental and destructive testing. Gas Controls from RIFLESPEED are the ultimate solution to the problems of operating hard-use carbines in varying conditions configurations and environments. With complete control of the gas that's delivered to the action of your rifle with each shot you'll enjoy increased reliability reduced recoil reduced muzzle rise less aiming disruption less wear and tear on your rifle and improved accuracy. Set your RIFLESPEED Gas Control for ideal performance with light commercial ammo or higher-pressure milspec ammo. Dial your gas system in for ideal performance in extreme heat or frigid cold conditions. Enjoy optimal performance with or without a suppressor. With a properly adjusted gas system you can eliminate the need to use exceedingly heavy buffers. Once you experience the advantages of using a RIFLESPEED Gas Control youll never want to shoot anything else. Specifications for Riflespeed Gas Control .750in Assembly Block: Manufacturer: Riflespeed Color: Black Coating: QPQ Gas Block Journal Size-Diameter: .750 in Caliber: 6.5mm Grendel 7.62x51mm NATO 5.56x45mm NATO .300 AAC Blackout 6.8mm Remington SPC .308 Winchester .223 Remington Finish: Nitride Features of Riflespeed Gas Control .750in Assembly Block Tool-free adjustment Distinct numbered settings for easy status identification and repeatability Multiple lengths available for use even while tucked under extended handguards Modular design allows user-level configuration and maintenance Rotation limited to avoid possibility of unintentional disassembly Package Contents: Riflespeed Gas Control .750in Assembly Block Riflespeed US0170: RS7521 Gas Control Assembly Black Nitride QPQ 0.750in Diameter 2.1in Length