U.S. Bank has introduced a new credit card, the U.S. Bank Shield Card, with a 24-month 0% intro APR.The card offers an unmatched 0% intro APR on purchases and balance transfers for 24 billing cycles.After the intro period, a standard variable APR of 17.74% to 28.74% applies.U.S. Bank claims the U.S. Bank Shield Card provides the best and longest introductory APR offer on the market.