FWIW, Marlin has had only a single design of .22 auto-loading rifle in production since 1960.
Marlin has produced many several MILLIONS of them, at this date.
That one design, however, has carried about 15-20 different model designations over the years, according to config, finish and furniture as issued; and whatever brand names for various chain store customers like Sears, Montgomery Ward and others..
Some of the Marlin models are: 60/70/79/795/99/99M1/990/990L/995.
Your particular model, the 990, was so stamped from 1993-1997, IIRC.
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