7304-219 LOCKWOOD sighting level. For a long time it was unknown who manufactured or patented these as they were just marked "Patent Applied For" until one showed up a few years ago accompanied by a paper flier that attributed it to the Lockwood Brothers of Rochester, NY. (See article by Jim Gehring in the Fall 2020 Fine Tool Journal). This example is 12" long with brass end caps and brass top plate, like most has partial paper label that says "Patent Applied For." Vial wet, wood has a few scratches and dings otherwise nice. (PLH2526)