Product review (5 stars): Clean Freezer
These are absolutely the best for keeping freezers clean and odor free.  I've tried Arm & Hammer and other products, and hands-down, these will keep odors down and smell/ice clean.  NOTE:  The refrigerator version of this product is also a "must have" if you're trying to keep the smell of left-overs and other pungent smells under control.  These will last a good 30-60 days, and still out perform AH baking soda or other solutions.