The invention relates to use of a tetrafluoroethylene/perfluoroolefin copolymer applied as a primer powder in conjunction with a powder overcoat of tetrafluoroethylene/perfluoro (vinyl alkyl ether) copolymer, also known as perfluoroalkoxy polymer (PFA), which when baked onto a substrate gives superior and more durable adhesion of the coating system to the substrate. The quality of the adhesion is measured by a boiling water peel test.