This offer has expired. Get a free bag (3.5, 4, or 6-lb) of By Nature dog or cat food after rebate (up to $12.99 value). Just fill out the form to receive a link via email to print your mail-in rebate form. This rebate offer started August 10 and ends November 10. Don’t forget to save your UPC and original store cash register receipt to include with your form. You must mail in the required items before 12/31/10. You’ll find these products at stores including Petsmart.