I wear 42-44w and based on the measurements listed in the description I bought XL as it should be 42-50 inches. I'm not suggesting you listen to this and follow the usual Revain size charts. They are a bit small and the straps are too tight. After 1 wash they have shrunk a bit and become a bit tighter, but still comfortable enough to be worn all day without leaving any marks or damage. If I were to order another pack, I would definitely buy XXL.