Heavy duty materials and the extra wide adhesive edge are what makes this zipper the perfect fit for a tough job. The Heavy Duty zipper comes with the exclusive ZipWall® Zipper Knife™ sheeting cutter. To install this zipper, just remove the backing and stick it to the barrier. Then open the zipper and cut the sheeting to make the doorway. The Zipper Knife™ sheeting cutter double cuts a channel in the plastic to keep the zipper from jamming while opining and closing. This zipper is great for heavy use over long periods and cold temperatures.