Pentagon Shirts and Trousers: Pentagon t-shirts are perfect for using as undershirts or as training wear for military and tactical purposes. These quality, hard wearing t-shirts are made of 100% ring spun cotton making them very comfortable to wear for whatever purpose you require. Our collection of Pentagon trousers also provides you with examples of durable and high quality items of clothing ranging from general purpose through to heavy duty tactical trousers, all of which have been designed to provide full comfort and protection.