Oatey® 3" – 4" 500 DFU Sure-Vent AAV 3" x 4" Sch. 40 PVC adapter
Oatey® Sure-Vent® 500 DFU Capacity Air Admittance Valve's one-way valve is designed to allow air to enter the plumbing drainage system when negative pressures develop in the piping system.
Complies to ASSE Standard 1050 and 1051
For use as a secondary vent
One size approved to handle up to 4" vent pipe
Opens/closes as needed by building's plumbing system