4" Stainless Steel Hinged Flap Gate for PVC, CMP, HDPE | Agri Drain Color:Gray It features a 12" inside

It features a 12" inside diameter

This 15" version fits on the outside of Corrugated HDPE Drainage Pipe and is intended for heavier-duty surface conditions

This version is the 12 HPF configuration with 1" holes and is used where a lower hole-per-foot opening pattern is needed in the top section

Flexible Fernco coupling for secure drainage pipe connections between 18" PVC and 18" PVC

4" Stainless Steel Hinged Flap Gate for PVC, CMP, HDPE | Agri Drain Color:Gray It features a 12" insideHelp keep damaging water out of drainage systems with this 4" stainless steel hinged flap gate. It fits outlet ODs from 3. 85" to 5. 1" and is designed for PVC, Corrugated Metal Pipe (CMP), or Corrugated HDPE Drainage Pipe.