Oatey Sure Vent 1-1/2″ X 2″ in. Dia. x 1/2 in. Dia. PVC Air Admittance ValveOatey Sure Vent 1 1 2" X 2" in. Dia. x 1 2 in. Dia. PVC Air Admittance Valve. Brand Name: Oatey Sub Brand: Sure Vent Product Type: Air Admittance Valve Size: 1. 5 in. End 1 Diameter: 1 1 2" X 2" in. End 2 Diameter: 1 2 in. Material: PVC Packaging Type: Bagged Complies to ASSE standard 1050 and 1051 For use as a secondary vent One size approved to handle up to 3 in. vent pipe Opens closes as needed by building's plumbing system 20 DFU Schedule 40