Bell System Blue Color Sample 500 Set
1954
Australian PMG 300 Series Wall Phone
1939

Siemens W48 Phone

1948 - 1961

About The Model W48

Siemens' main desktop phone model starting in 1948.

Wikipedia

The W48 was a version of a desktop telephone lineage developed in the mid-1930s in Germany by Siemens & Halske for the German telephone and postal administration.