This is a very nice used 8" long, heavy duty (thicker jaws) adjustable wrench marked "DIAMOND CALK HORSESHOE CO. DULUTH MINN 8 FORGED DIAMALLOY TOOL STEEL DROP FORGED MADE IN U.S.A." in raised cast lettering. There is very minor wear noted on the jaws, not bad, in good useable condition, with very good jaw alignment. The pitting on the handle appears to be an as cast issue as it is mainly on one side and not around the jaws area.  A nice clean vintage wrench from the 1920's era!  Note:  This is the wide jaw version, with jaw with of .36-.49", versus the lighter duty model which is about .60" thinner.  Also note this model does have the diamond inside the horseshoe logo on it, and also has the larger diamond DIAMALLOY inside it.