Photograph of letter carrier in Mailster vehicle
City letter carrier seated in a three-wheeled “mailster” motor vehicle. Carriers used these vehicles to carry the ever-increasing amounts of mail that were being delivered to American households after end of the Second World War. The mailster worked best in temperate climates and on even terrain. In other areas, they sometimes did not work at all. Carriers in colder climates could be immobilized in as little as three inches of snow, and they also complained of the vehicles’ inability to heat properly. The three-wheel design left mailsters susceptible to tipping over if cornering at speeds over 25 miles per hour or if caught in a wind gust. One carrier complained that his mailster was tipped over by a large dog.