I was struggling to figure out the best way to keep my dog food fresh. I buy 40 pound bags of dog food. Experts recommend storing dog food in its original packaging as the pouch is for the food inside. Standard pocket clips are too weak. These heavy duty clamps work great. I open one or two types of dog food at a time and put the opened bags in a large plastic bag. When I'm done feeding, I roll up the top of each pouch and squeeze out the air. I use two or three clips on each bag to keep food fresh. When I'm done, I put the lid on the bag and seal it so my two Great Pyrenees don't get stuffed. :)