The 1930s was the breakthrough year for functional design in Sweden. A quest for simple and functional forms, honest and clear materials and, not least, simplified mass production paved the way for a whole range of new building materials.
On the fittings side, especially the door fittings changed. Nickel-plated surfaces were used instead of brass, which had to be polished to keep its shine. The handles were now made of easy-to-clean bakelite instead of wood. And the new long plates combined the two functions of rosette and key plate in a single plate.
In addition, the door locks were standardized so that all the prints fit all the locks and all long plates were made with the same distance between the print and the hole for the key.