The Oatey Sure-Vent 1-1/2 inch PVC Air Admittance Valve is a two-piece set that includes an adapter. This valve is designed with a 1-1/2 inch interior diameter and is made of PVC material. It features a smell-proof construction and has an unfinished finish. The unit is 6 inches long and 2 inches wide, perfect for providing air admittance in plumbing systems. With the trusted Oatey brand, this valve is a reliable solution for your plumbing needs.