Men's Boxer Briefs: Are they boxers or are they briefs? Probably the least understood silhouette in the world of men's underwear in the UK. Boxer briefs are often confused with the boxer trunk style, which has a much shorter leg length, or the boxer short, which has a much looser fit and is often fabricated in a woven cotton. And boxer briefs are also mixed up with the men's briefs shape, which has a minimalist design in the leg. But boxer briefs are a unique style.