

Ships same day if ordered by 12 pm
Manufacturer pricing rules prevent us from advertising our discount — no account or email required to see it.
Secure Payments
Easy Returns
Expert Advice
Fast Shipping
The OATEY 238-703 is a 3-inch plastic knockout test cap used to pressure-test and air-test drain, waste, and vent (DWV) piping systems. The cap seals the open end of a 3-inch pipe, allowing the system to hold pressure during inspection. A knockout center lets the installer pop out the plug once testing is complete, restoring flow without removing the fitting. Licensed plumbers use this cap during rough-in inspections to satisfy local plumbing code test requirements.
This test cap is sized for 3-inch plastic pipe and is suited for residential and light commercial DWV applications. It is commonly used during new construction and remodel rough-ins where the authority having jurisdiction requires a witnessed pressure or air test of the waste and vent system before walls are closed. The knockout design saves time by eliminating the need to cut out a temporary cap after the test passes.
Designed as an OEM-style test cap for 3-inch plastic DWV piping systems. Compatible with standard 3-inch PVC and ABS drain, waste, and vent pipe configurations typical in residential and light commercial plumbing.
Installation is performed by a licensed plumber during the rough-in phase before inspection. Ensure the pipe end is clean and free of burrs before seating the cap to achieve a proper seal. Follow local plumbing code requirements for test pressure and duration. Remove the knockout only after the test has been witnessed and approved by the inspector.
Thanks for subscribing!
This email has been registered!