Fernco 1-1/4"x1-1/4" Flexible Coupling with 2 Stainless Steel Clamps. This corrosion-resistant, flexible, lead-free, removable, UV-resistant, underground-rated coupling connects cast iron or plastic to cast iron or plastic. It has a maximum working pressure of 4.3 psi, a maximum working temperature of 120 degrees Fahrenheit, and a 1-year warranty.