Bus Number 3100 (1956) was the first air-conditioned bus in the United States used for public transportation. The bus was designed and built as an experiment, with this single example was purchased by the Fifth Avenue Coach Company about a year after its manufacture. It has other features first introduced in the 1950s: a push type rear exit door, wrap-around seating in the rear portion, soft seating, and fluorescent lighting. After two decades of passenger service, this vehicle was assigned to the Transit Police; it was retired from all service in the mid-1970s and restored to its original appearance in the early 1990s.