The PP-90M1 (Cyrillic: ПП-90М1) is a 9×19mm Parabellum Russian submachine gun developed by KBP Instrument Design Bureau in the 1990s.
It features a 64-round helical magazine, and other than sharing a manufacturer is unrelated to the similarly named PP-90M.
The weapon may also be used with a 32-round box magazine if desired, although it might require the need of a stick magazine adaptor.
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