According to Nick Sullivan at Esquire, "In the U.S., blazer has come to mean anything that has sleeves and lapels and is worn with unmatched trousers, but there are key differences. He noted "...a blazer usually means a patch pocket, navy blue jacket with gold or (occasionally) silver buttons." Regarding the suit jacket, Sullivan adds, "Finally, a suit jacket will always be made of the finer stuff, i.e., worsted wool, and smooth to the touch." Remember, this is a general guide and the differences are not always so easily defined.