The SLR Rifleworks Sentry Adjustable Set-Screw Gas Block ensures that AR-15 shooters have the ability to fine-tune their gas system for optimum operation. The SLR Rifleworks Sentry Adjustable Set-Screw Gas Block is constructed with a simple metering system that doesn't use springs or balls and is adjustable through the use of an included tool.

• Machined from 4140 steel
• Features QPQ Melonite finish
• Comes in .625, .750, .875 and .936 diameter sizes

The SLR Rifleworks Sentry Adjustable Set-Screw Gas Block is equipped with two set screws that lock the block into the barrel for an ideal gas seal.