Screwy agb - Luth-AR AR-15 Adjustable Gas Block .750 ID

As far as fit and finish it's fine. It has + and - indication symbols engraved around the gas adjustment set screw. My disappointment has to do with the location of the locking set screw (the 4-40 set screw that applies tension on the gas adjustment screw). It's on the shoulder side, not the muzzle side, of the gas block (look at the picture, it's visible). I put just enough tension on it so I can make gas flow adjustment, because the lock set screw is unaccessible with a handgaurd installed. The gas block does regulate gas, it does work.