Looking for the latest 5 Seconds of Summer Tank Tops? We have them here – just in time for summer! 5 Seconds of Summer (5SOS) is a boy band that debuted in 2014 in America. They are based in Australia and are managed by a company called 5 Seconds of Summer Shop. The 5SOS band members include Ashton Irwin, Luke Hemmings, Calum Hood, and Michael Clifford. All of their shirts feature the word “Summer” either on the front or around the neckline.