The Montblanc Pix 36 was made from 1961 to 1970. It is a propelling pencil in which a push-button at the top end advances the lead.
Pencils of this period carry neither a serial number nor a date; the model number on the centre band or on the barrel is therefore the decisive feature for dating. At Montblanc, Pix has been the name for pencils with a push mechanism since the 1930s and was carried on over decades and across several series, so that the individual versions can be told apart only by their number and by shape, clip and the colour of the fittings.