Ade Advanced Optics Table Bench Block for 9mm Glock, Black&nbsp; This a gunsmith tool to clamp a pistol firmly for effective cleaning, assembly, and repair. It is NOT a gun part Held in place by the magazine catch Allows for Both Hands to Work on the Pistol for Maintenance and Cleaning Provides a "third-hand" to work on and install parts to Lock pistols in 9mm/.357Sig/.40SandW