The Superlative Arms gas piston block redefines adjustability with its patented Bleed Off Mode, which redirects excess gas out the front rather than limiting flow, resulting in more consistent pressure management. 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 3/4 inches x 1 inches clamp-on QPQ melonite 416 stainless steel piston gas block Left-handed, fully automatic AR-15 bolt carrier, dark DLC coated, 8620 steel Rifle gas system/operating rod length