Fernco 1006-66 1006-66 6 in. PVC Concrete to C.I. or Plastic Flexible Coupling

The Fernco 1006-66 is a 6 inch flexible coupling made to transition concrete pipe to cast iron or plastic pipe. It is the fitting you reach for when a concrete sewer line meets a PVC or cast iron run and the outside diameters do not match.

Both ends are sized for 6 inch pipe, but they are not the same pipe type. One side takes 6 inch concrete pipe and the other takes 6 inch cast iron or plastic. Nominal 6 inch concrete pipe has a larger outside diameter than 6 inch cast iron or PVC, which is exactly why this coupling exists.

For a concrete line, yes, on the concrete side. The 1006-66 is built to mate 6 inch concrete pipe to 6 inch cast iron or plastic, so it is the standard way to splice a PVC repair section into an existing concrete lateral. If both ends of your repair are the same material and diameter, a straight 6 inch same-size coupling is the simpler part.

No separate gasket. A Fernco flexible coupling is one elastomeric sleeve with the stainless clamps already on it; you slide it over the pipe ends and torque the bands. What you do need to supply is a properly cut, clean, deburred pipe end on each side so the sleeve seats.

Order Fernco 1006-66. That is the manufacturer part number and the single model offered, so there is no size or material option to specify beyond it.

An unshielded flexible coupling like the 1006-66 is used on gravity drain, waste and vent lines, including buried sewer, where it is properly bedded and supported. Where local code or the inspector calls for a shear-resistant joint, or the joint is in a suspended or above-grade run carrying load, use a shielded coupling with a stainless steel band instead.