Here is an offer for a FREE bag of Hills Science Diet Dog Food from Petsmart. From 2/17/2012 to 2/20/2012 Petsmart will have Hills Science Diet 4-5 pound bags of dog food on sale for $6. When you sign up for Hills Science Diet on the link below, you will get a $8 off coupon making a bag FREE! Tip: If you hit the back button after printing, you can sometimes print 2 of these coupons. If you have more than one computer, you can usually do that over on another computer! The $8 you can also get off cat food, but it isn’t on sale. My cat has special food that is $17 per 4lb bag, so I will be using the cat ones as well to stock up at a great price!