This is an Optimus 200 lantern from around the mid-1940s. It appears to be the same variation as this one of @Michel. It has the pump positioned so that it sits to the right of the central pickup tube (@Nils Stephenson). The top cap of the hood is held in place with a single screw at the centre. The lantern had been fettled by Vic Tipman, from whom I bought it, but I did some tweaking and a bit of painting before getting it going again. It was not fully pulled down. "Stockholm" The pump locks. Fuel level reader. The nipple is stamped "2". "Optimus 200/Made in Sweden" "Optimus/200CP" I painted over Vic's black with siiver galvanising paint. "200/250". This is the burner that came on the lantern. "Germany" Up and Running From Catalogue N0. 1700E This is a very good lantern! Cheers Tony