Prior to the late 1930s, tee shirts were worn as sportswear, underwear, and military wear -leaving no practical need for a chest pocket. The first ad for a tee shirt as casual wear appeared in a 1938 Sears catalogue, as the "GOB" style shirt - a reference to sailors. It was followed shortly by a 1939 ad for a long sleeve pocket tee as well as one with striped contrasting trim as seen in the photos provided. This is an early 1940s pocket tee with striped contrast trip on the sleeves and neck.