The Seekins Precision Adjustable Gas Block (.750) allows the user to fine tune the rifle's gas system for smoother cycling and operation to allow faster follow up shots, target acquisition and reliability. The Adjustable Gas Block is field adjustable simply by turning the gas regulating screw in to lessen the amount of gas and out to add more gas. Use the brass set screw to lock the setting in place. The overall height is 1.37" with left to right dimensions at .94" which will fit under most hand guards yet be easy to adjust. The gas block is Melonite coated to reduce wear and corrosion as well as it makes cleaning easier, as carbon build up will not adhere to the non-reflective coated surface as much as it does on standard Parkerized finishes.