The adhesive film is used between the PE core and aluminum to well adhere these two parts. This material is very important as its quality will result in whether the aluminum plate will be peeled off from the PE core easily if the adhere film is not good. Therefore we use adhesive film produced by Dupont that is produced from U.S.A. This material provides the perfect bonding between aluminum skins and the polyethylene core. The bonding will stand the test of time under extreme weather elements.