The biggest difference here was the 3 and 13 were made of metal and wall mountable
Number 5 - The predominant dial of the 40's and 50's was replaced by the number 6 for a more universal fit
The newer phone had coin slots for nickels
The line cord has a modular connection to facilitate a modern connection to your wall jack
They developed groundbreaking telegraphic equipment
2500 - Black automobile The biggest difference here wasHistory After eight years, 2500 sketches, measurements of 2000 faces, and the preparation of endless clay models and lacquered plastic castings, the famed industrial designed, Henry Dreyfuss finally arrived at the form of the new "universal" set, the Model "500" in 1949. The Model 500 and it's sister wall phone, the 554, were the most popular telephone set ever designed, and they remained in production for 35 years without essential change. Colored