Abstract: A flexible extrusion molded flange for securing bathtubs and the like to surrounding walls while simultaneously providing a moisture barrier therebetween. The flange snaps on to the vertical edge and horizontal deck of the tub. The flange includes a vertical back strip for securing the flange to a stud wall, a drywall sealing lip forming a moisture barrier between the tub and the drywall, a finish wall sealing strip for sealing and aligning the finish wall, and a tub edge securing strip for receiving the edge of the tub. Miter cut corners and silicone sealants enhance the flange's moisture barrier properties.