Long underwear is the most suited men’s underwear style for cold weather months. Also known as long johns and thermal underwear, long underwear is a distant relative of a product originally designed for women in the 19th century. The father of long underwear, the union suit, was originally designed for women seeking undergarments that were less restricting than their Victorian lingerie. The one-piece garment quickly caught on with men because of its function and style and was used by working men well into the twentieth century. The one-piece union suit was popular for it’s thermal qualities and rear flap, otherwise known as the “access hatch,” “drop seat,” or “firemen’s flap.”
The union suit quickly evolved into long underwear, produced as a two-piece garment, and is now a staple in any man’s cold weather wardrobe. Long underwear is often produced in form fitting fabrics with moisture wicking properties for optimum comfort and warmth. Though long underwear is produced in a variety of fabric combinations, the most common is a cotton and polyester blend fabric made with a box-weave texture, for optimal warmth.
Long underwear has, for the most part, lost it’s rear flap and is no longer a substitute for women’s lingerie, of course. It is, however, a fashionable winter accessory that is being increasingly incorporated into men’s underwear offerings in a variety of colors, fabrics and designs.