This has been of interest for many years and a worthy topic. A Staffan recent comment: From the Stockholm-area based stove manufacturers, at least parts of the Radius (Stockholm), Optimus (Upplands Väsby) and Sievert (Sundbyberg) factories still remain as buildings albeit in modernized form and with different purposes.... Lighthouse comment: "What remains of the Lux buildings are the two workshop buildings... c. 1910 Stockholm area (and Upplands Vasby to northwest) WIP Locations. Not sure I'll get there (others welcome), a map showing locations would be a next step. Interesting to see the close proximity the competition was to each other c. 1910 c. 1910 / Early Locations, per current (google searchable) addresses: Optimus #1: Trässman & Pettersson 1899 to-> Optimus factory #1. Hantverkargatan 87, 112 38 Stockholm, Sweden Optimus #2. Optimusvägen 12 , Upplands Vasby Lux Primusgatan 116, Stockholm 112 67 Sweden images EAST Essingen island Primus Primusgatan 18, 112 62 Stockholm, Sweden images WEST (NW) Essingen island Radius: Radiusbacken 15, Tellesborg, Sweden image Sievert / Nyberg: c. 1900 Nyberg solder lamp (&stove) factory *???? Sundbyberg, Sweden 1922 the solder lamp factory was taken over by AB Max Sievert *???? Sundbyberg, Sweden source for images and in 2020: "C.R. Nybergs original factory building..." credit Ross, Staffan, Bo, Frank and others wiki ??? :"Sundbyberg developed as a city largely thanks to [3 Sievert brothers and the] Sievert’s *three factories there." *Of the 3, Nybergs company/factory made stoves & blowlamps. KFE, Erikssons ????