Petromax

The Petromax lamp was developed in 1910 by Max Graetz at Ehrich & Graetz. The first Petromax was a hanging lamp, today's most well-known version in the shape of a lantern has been around since 1922.
Petromax manufactured pressure lamps, stoves, and hanging lamps for indoors and outdoors in various sizes.
 
From 1933, Ehrich & Graetz AG also concentrated on the production of war goods. After the Second World War Graetz AG built a new factory in Altena / Westphalia to produce Petroleum pressure lamps.
 
In the 1960s at least 80% of the lamps were exported. Demand collapsed in the 1970s. To reduce production costs, production was relocated to Portugal, where was manufactured Petromax, Geniol and Hipólito lamps, which had different names but were technically identical. With the aim of further reducing manufacturing costs, production was eventually relocated to China.