This is a Real Avid Tool known as the Smart Lock, model AVSLBG.
This clever design combines the ability to lock the AR15 upper open while perfectly aligning cleaning rods inside the barrel. The industry-first pivot-locking arm securely holds the upper open at an optimum angle for cleaning the bore. The Smart Lock Bore Guide protects the chamber and bore from accuracy-robbing damage by preventing the cleaning rod from bowing and rubbing the bore throat. By properly aligning the rod" it is easier to push tight patches through the bore. It reduces solvent and gunk from entering the action while scrubbing a dirty bore. The included Pivot Lock holds the gun open while cleaning the star chamber.
Features:
Pivot-Locking Arm
Protects the Chamber
Reduces Solvent and Gunk from Entering the Action
