That’s a Jeepney in the Philippines. They’re a very popular form of transportation around the country, says Jens Meiners in Car and Driver:
Jeepneys are the Philippines’ most popular form of public transportation, and they are a pure anachronism. They got their start as Willys Jeeps left behind when American GIs departed the Philippines at the end of World War II. Filipinos then began recycling them as buses with bodies made from galvanized or stainless steel, fabric covers instead of side windows, and longitudinally mounted benches with room for 20 (or more) passengers. Those beginnings are still apparent, despite the cheeky Mercedes-Benz stars affixed to the front of many modern Jeepneys.
This postcard took almost two months to arrive in the U.S. from Manila. I wonder if it was delivered on a Jeepney.