Influenza vaccines, also known as Flu shots or flu jabs, are vaccines that protect against infection by influenza viruses. Every flu season, many locations offer flu shots to their community. Flu Shot Here feather flag. This Half Sleeves  12ft. flag is in blue color with the text  “Flu Shots” in yellow. Our feather flags are easy to use and take only minutes to set up. Place this feather flag in a strategic place and let it show everyone that you’ve got Flu shots center or clinic ready to help patients who suffer from flu. Feather flags are a proven marketing tool to help bring customers and increases your sales.