4917 is a 3.34 mil, double coated polypropylene film used as a re-openable closure system for filmic bags. It is transparent and has a widely different adhesion values on each side. This produces a smooth open and close action without leaving adhesive residues. The red polypropylene film liner and backing is easily cut with the hot wire of bag making machines. The acrylic adhesive system is aging resistant and offers high adhesion values on each side.