The nib engraving 4810 is borne by every Montblanc gold nib and says nothing about the model; the 585 hallmark confirms 14-carat gold, the M the nib width Medium. With a length of only 13.5 cm a 146 LeGrand can be ruled out; smaller Meisterstücks such as the 144 Classique come into question. A reliable authenticity check is not possible from verbal descriptions alone, which is why purchase from an authorised specialist dealer or from reputable mail-order sellers such as scription.de is recommended. For eBay purchases collectors advise requesting high-resolution photos of nib, ink window, cap rings and clip and matching them with detail shots from relevant collector pages. Cartridge compatibility is given on Meisterstücks only with a few smaller models; classic Meisterstücks are piston fillers.