9x19mm parabellum  caliber,  marked  “FABRYKA BRONI -RADOM” on the left side of the slide along with the EAGLE stamp and dated (1939),  Finished blue with brown plastic “FB” grips.  In very near mint condition retaining 98-99% original blue, excellent grips and bore.  Pre-invasion mfg and one of the best conditioned examples I have seen.