US Patent 7424754 Water-proof joint for tub and shower surrounds

A molded tub and surround which is formed of a multiple of portions. Wall portions meet a tub portion at a joint with a retaining ledge which extends inward toward a tub bowl from a flange. A ledge interface within the bottom of the wall portions engages the ledge. An angled interface surface is located directly in front of the ledge and slopes downward toward the bowl. A shallow interface within the bottom of the wall portions engages the angled interface surface.