The JPGS-9D is our minimized small bore design intended to mount underneath many hand guard models on the market. Its two-piece design allows for easier installations even on barrels with pin-and-weld muzzle treatments. This model features our new click-adjustable detent system for precise adjustments and secure retention of your gas screw. Never lose you gas setting or screw. Features: Click-adjustable detent system for repeatable setup and secure retention of gas setting Six clicks per rotation of gas screw for finer adjustments Split yoke design for easy installation even on pin-and-weld barrels Easy to access side gas adjustment Internally retained detent components means no lost parts Specifications: Barrel Diameter: .750 Material: 416 stainless Finish: Black Weight: 2.37 oz. Length: 1.28" Height: 1.23" (overall), .78" (over bore) Width: 1.16" Attachment: 6-32 x 3/8" socket head screws, T15 Torx drive (included) (includes 5/64 x 5/16 roll pin for gas tube installation) Adjustment: 8-32 set screw, 5/64 hex drive (included)