Wall phone of the Heemaf brand. The telephone is black lacquered and varnished metal with a bakelite handset and dial. The telephone has extension number 248. This phone hangs in the entrance hall of the Sonneveld House. This telephone was one of ten devices for telephone traffic in the house. There were also two telephones for outside traffic. The telephone was part of the Siemens and Halske house installation, which consisted of black wall models and black and white table models. A house system was not a recent invention in 1933; it was mostly purchased by businesses. For private use, however, it was a great luxury. House Sonneveld was completed in 1933 and was built for the Sonneveld family to a design by the architectural firm Brinkman and Van der Vlugt. They were also responsible for the interior, working closely with W.H. Gispen.