An apparatus for continuously treating metal strip of aluminum, an aluminum alloy, a nonferrous metal, or a nonferrous-metal alloy, has at least one heat-treatment device through which the metal strip passes in a strip-travel plane in a travel direction without contact from an upstream inlet end to a downstream outlet end and having a heating zone at the upstream end and a cooling zone formed by a row extending in the direction of at least two cooling subzones. A strip-centering device between the cooling subzones adjusts a position of the metal strip in the strip-travel plane and transverse thereto.