Smith-Blair EZ-W Restraint Couplings for water service are designed with push on gaskets and engineered to simplify installation, restrain the pipe joint and ensure a tight seal. EZ-W Couplings can be used to connect IPS PE to steel pipes 1" through 12" diameters and ductile iron to IPS PE, PVC or steel pipe, 3", 4", 6", 8" and 12".