Our Puerto Rico flag from our U.S. Territories flags collection at United States Flag Store are available in sizes ranging from 4 inches by 6 inches to 6 feet by 10 feet. Like the U.S. flag, Puerto Rico's flag is red, white and blue. Five alternating horizontal red and white stripes create the flag's backdrop. A blue isosceles triangle on the hoist side has a white, five-pointed star in the center.