Fernco 3"x1-1/2" Flexible Reducing Coupling with 2 Stainless Steel Clamps. It is used to connect cast iron or plastic to cast iron or plastic. It is corrosion resistant, flexible, Lead-Free, removable, UV resistant, underground rated, and underground use. It has a maximum working temperature of 140 degrees Fahrenheit and a maximum working pressure of 4.3 psi. It is ASTM C1173, CSA B602 and D5926 Specified. Series 1056 designed for cast iron, plastic, copper, steel or lead.