This Uni-Syn Model 4B Carburetor 4bbl "Four Bore" Tool synchronizer was rescued from a long-dormant speed shop auto parts store along with many other new unused NOS tools and parts. I would say that it's slightly used at best. Hard for me to tell with the storage patina from decades of sitting on a shelf. The box is an early version and not perfect. it has a surface cutout on face. This tool seems to be from the beginning of 4- barrel carburetors in 1952. Examine photos closely. No instructions. Great item for mancave shelf shop movie prop advertising memorabilia.