The M4 bayonet is the USGI bayonet for the M1 Carbine of WWII, Korea, and Vietnam fame. This particular one has "US M4 BREN-DAN" stamped on the hilt. This would place it's production time somewhere around 1944-45. It is in very good shape but, unfortunately, the previous owner decided to sharped the edge and thus the "Parkerizing" (phosphate finish) is gone for about 1/16" at the edge. No sheath/scabbard is included but any M8 or M10 series sheath should work fine.
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Price: $40. Will consider trades.