If there is not some marking on the slide, say Mark V, or something then I would think they have referred to it as their 1911 pistol. I know these came in 45, 38 Super and 9mm but I don't know the official name of the models. Possibly 1911 Crazy could help you out (if he sees this post) - he was recently working with one in 38 Super and he might know how to discern the model #s. HTH.