Refinement of Syrac's original adjustable gas block enables the shooter to fine-tune gas flow and rifle performance in the field. Designed to fit under free-floating handguards, the block secures to the barrel with two setscrews. The Gen II model eliminates the Gen I's release button, so you simply turn the gas adjustment setscrew with the included Allen wrench to one of 18 pre-set click detent positions. Click detent automatically locks in your setting; also makes "dialing in" predetermined settings for different loads easy. Standard Low-Pro models have setscrews on the underside; requires dimpling of the barrel. Clamp-On model wraps around the barrel and is secured with two side-mounted hex head cap screws.

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