The Waste Couplings are a type of pipe fitting only used in bathroom plumbing fittings. The regular design of the waste coupling has full threaded surface with the hollowed flange to flush the water out from the basin or sink. Couplings are designed to connect two shafts and transmit torque in a rotary motion from one piece of equipment to another. Couplings are rigid or flexible according to the alignment accuracy and torque requirement. The coupling is a mechanical component that connects two rotating shafts such as the driving shaft. The Waste Couplings are very useful.