You can do things like opening the bag to verify CO2 content without cutting and resealing. The clamp is made of two plastic pieces with a bolt and nut on one end that keeps them together. The nuts and bots are NOT included, but are available at most hardware stores. Use size 8, 10, or 12 bolts that are 5/8″ long with nuts to match. Simply fold over the top of your bag, snap the clamp in place and you are ready to go.
The video below shows exactly how this clamp works.