Wal-Mart Stores officially introduced its co-branded credit card on Monday (AA, Sept. 30), the Wal-Mart MasterCard from Chase. It will feature a fixed annual percentage rate of 14.48%, which it said was 3% lower than the average APR for other credit cards. There will be no annual fee. An introductory offer through Dec. 31 includes a $10 certificate good on one purchase of $50 or more at Wal-Mart. Applications will be available beginning Oct. 14; national TV and print advertising and direct mail is expected to begin this week. Agency is GSD&M, Austin, Texas.