Chinese AKM Type II Steel Bayonet and Scabbard.
According to the worldofbayonets.com website, this knife bayonet was manufactured for use with the semi-automatic 7.62 mm. AKM assault rifles commercially exported in the 1980s by Polytech and NORINCO (China North Industries Corporation).
Essentially, a copy of the Russian 6X4 (AKM Type II) bayonet, except that the sawback and wire-cutter features have been eliminated.
This example has a black plastic grip and scabbard body. This example is missing the chromed steel belt hanger provided on the earliest U.S. imports.
There is no evidence that the People's Liberation Army ever used this bayonet.