A 2x1-1/2 DWV coupling is a plumbing fitting used to connect two sections of pipe in a drainage, waste, and vent (DWV) system. It has a 2-inch opening on one side and a 1-1/2 inch opening on the other, allowing for a smooth transition between different pipe sizes. Made from durable materials, this coupling ensures a secure, leak-free connection for efficient wastewater managemen