Eskilstuna is the brand I had and had posted about.
"The city grew enormously during the Industrial Revolution and became one of the most important industrial cities of Sweden, earning the nickname "Stålstaden" ("The City of Steel"). Aside from firearms, the city also produced cutlery, scissors, keys, machine tools and precision instruments. As a tribute to the steel industry, the figure of a steel worker is included in the city's coat of arms. Eskilstuna is sometimes called The Sheffield of Sweden, Sheffield being a (much larger) industrial city famous for the quality (and quantity) of the steel produced there. Both cities at their peak were home to numerous different companies involved in steel production."
Many tools were produced there, and many more using steel from there.
The wrench design has been reproduced by a bunch of makers.