About This Phone
The 500 was the Bell System's mainstay phone for decades, first as a rotary dial and then push-button, in many colors. Like its predecessor, the WE 302, it was designed by industrial designer Henry Dreyfuss. As an improvement over the 302, the dial markings were placed outside of the fingerwheel holes for improved legibility. The slightly larger base provided room inside the 500 for an adjustable bell ringer and enhanced electronics. The more angular G1 handset design replaced the curves of the 1930s-looking F1.
Variations: In the early 1950s, the Bell System began to promote the new 500 sets in "designer colors" for an affordable one-time non-recurring charge at the time of installation. The light blue 500 set shown has the rare and special 'mushroom' night-light just above the number 4 on the dial.
Wikipedia
The Western Electric model 500 telephone series was the standard domestic desk telephone set issued by the Bell System in North America from 1950 through the 1984 Bell System divestiture. The successor to the model 302 telephone, the model 500's modular construction compared to previous types simplified manufacture and repair and facilitated a large number of variants with added features. Touch-tone service was introduced to residential customers in 1963 with the model 1500 telephone, which had a push-button pad for the ten digits. The model 2500 telephone, introduced in 1968, added the * (star) and # keys.