The HBT uniform was general issue to all personnel in the US Army thus the number produced was several million pieces. The garments were utilized throughout the entire conflict, in all theaters. Wear depended on the weather- in hot climates, this was the main uniform, worn often by itself. In cooler areas, the was worn in conjunction with the OD's (wool shirts and trousers) and field jackets. Some units and troops chose to wear the top over their field jackets- the best known photographic example being the 4th Division troops on Utah beach. Others worn it underneath other uniforms- American soldiers were famous for their habit to improvise and customize their uniforms and gear in the combat zones.
Jackets were frequently worn tucked in at the waist.
All patterns and both colors were issued and worn through the end of the War, and some were later utilized in Korea.