Unlike conventional systems that restrict gas flow, Superlative Arms' patented Bleed Off Mode vents gas forward through the block - an innovative solution that enhances control and reduces fouling. Gas adjustment (patented) - features 30 fixed positions located at the front of the block Bleed-off port (patented) - located at the front of the block, designed to vent forward, directing emissions away from the operator 0.625 inches x 1 inches solid set screw QPQ melonite 416 stainless steel piston gas block Right hand, full-automatic AR-15 bolt carrier, dark DLC 8620 steel Carbine gas system/operating rod length