My husband is a big guy and when he does a lot of walking around when we are traveling he gets horrible chaffing. He wore these while on a 15 day trek through the Himalayas and surprisingly- no chaffing! The men's underwear run true to size, unlike the women's. My husband wears an XL in American Eagle boxers and the XL ExOfficio boxer briefs fit perfect. He has two pairs and I'm going to get him two more. They are very light weight, stench resistant, and easy to wash. Two thumbs up!