I have a Primus 1320 (for sprit). I says AP34 at the underside of the fueltank, and I´m aware that it means 1951, but the green enamelled top is the type in one piece and no nut, and without the steel shield for the mixingtube inside. Is that consistent with the produktion year. Regards Niels Chr.
As far as I am aware, the change happened during 1954 together with other major changes for the Primus company that year. Having said that, I have just found a 1020 from 1951 (AP 34) that has the smooth top and no plate on the burner. I am sure this is an ex military lamp so can have been serviced and had parts replaced (it has an Optimus filler cap) at a later date.
