I believe the name "P-01"" was to satisfy the requirement that CZ firearms have a unique name if sold in certain markets for example in North America. If you go to CZ UB, the CZ75D Compact is listed as 1 model but offerred either w/o rail (PCR) or w/ rail (P-01). In CZ USA these are 2 separate models with different name. Also regarding the NSN (NATO Stock Number) on the P-01, it is more of a marketing gimmick since all firearms used by NATO allies as well as any supplies are given a stock number. The colts, barrettas and glock used by the US military had NSN it was just not engraved on the firearm.