Pakistani Fantasy Knuckle Knife, likely from the 1980s.
During the late 1970s and 1980s, Pakistan was a maior exporter of "fantasy" and "novelty" knives that flooded flea markets, gas stations, and mail-order catalogs (like the famous BudK or Edge Co catalogs). These were often marketed as "assassin" or "survival" knives but were primarily designed as decorative conversation pieces.
The piece is very heavy and is metal plated. It needs to be cleaned up a little bit to make it shinier. But because it’s plated on top of steel it’s not designed to actually cut something. It is not safe for children. You won’t be able put a sharp blade to it, but because of its weight it is not a toy.