In 1915, a competitor, Bradley, Voorhos and Day brought out a light cotton union suit made of a fabric called nainsook. It was cut and sewed, not knit. The garment was sleeveless and had quarter-length legs. The very lawsuit Coopers had lost now brought benefits. Cooper could safely copy the B.V.D. design, which it did, incorporating into its new lightweight union suit the familiar Klosed Krotch.
Underwear has fashion changes, too.
A major change occurred after World War I, when young veterans began wearing the sort of knit skivvy shirts and separate cotton shorts they had worn in the Navy. By 1930, the traditional union suit was considered an old man's style. There were even more startling style changes ahead for Cooper's underwear business. In the post-World War II Jockey era, Testard created the bikini brief and promoted colored underwear, well before it became vogue. The Depression years wiped out much of the wealth Johnson had earned from his Klosed Krotch design, his granddaughter says.