Presently described is a composition comprising at least one first divalent unit comprising a pendant perfluoropolyether or perfluoroalkyl group; at least one second divalent unit comprising a pendant phosphorus-containing acid group; and at least one third unit comprising a terminal or pendant alkoxy silane group. Also described is a coating comprising the composition described herein dissolved or dispersed in a solvent and a method of providing a coated article or surface. Such method is particularly useful for providing corrosion protection to a metallic surface.