US Patent 10166658 Multi-purpose wrench for servicing a firearm

A wrench and a method for performing gunsmithing operations is disclosed. The wrench may have a first end and a second end. The first end may have an integrated two-sided castle nut and flash hider wrench aperture, and the second end may have a tool interface. The aperture may have a plurality of raised elements for engaging indentations in a castle nut, each of the raised elements extending at least one of inwardly from a wall section of the aperture and upwardly from a first face of the wrench. The aperture may have a flash hider cutout portion.