Fernco 4"x3" Flexible Reducing Coupling connects clay pipes to plastic or cast iron pipes, providing a secure and reliable connection for drain, sewer, vent, and waste applications. It features two stainless steel clamps for easy installation and a pressure rating of 4.3 psi. With an operating temperature range of -30 to 140 degrees Fahrenheit, this coupling meets ASTM C1173, CSA B602, and D5926 specifications.