Good deals on Kraft Macaroni & Cheese Crackers at Amazon. Use promo code BCKSCLO9 to receive up to 40% off on purchasing 2 or more items. 2 items are eligible for 20% off, 3 items for 30%, and 5 items for 40% off.  Shipping is $0.99, or free on orders over $25.  Here is a screenshot for your reference.  Some examples are listed with prices shown reflecting the 20% discount.

• Kraft Macaroni & Cheese Crackers, Cheddar, 8-Ounce Boxes (6-Pack) for $13.66
• Kraft Macaroni & Cheese Crackers, Mild Cheddar, 8-Ounce Boxes (6-Pack) for $13.66
• Kraft Macaroni & Cheese Crackers, White Cheddar, 8-Ounce Boxes (6-Pack) for $13.66