{"product_id":"500-dfu-stack-air-admittance-valve-adapter-for-pvc","title":"500 DFU Stack Air Admittance Valve Adapter For PVC Schedule 40 Straight Vent 3 To 4 Inch 160 Branch Black White Finish ASSE 1050 1051 Compliant DIY Friendly DWV Plumbing","description":"\u003cdiv\u003e500 DFU Air Admittance Valve Adapter for 3-4 in PVC DWV\u003cbr\u003e\n✔️ ASSE 1050\/1051 compliant, 3-4 in vent, 160 branch, black\/white unit \u003cp\u003eThe 500 DFU Stack Air Admittance Valve Adapter is a venting accessory designed for PVC Schedule 40 DWV systems. It serves as a secondary vent for 3 to 4 inch vent lines in residential or light commercial plumbing, helping to equalize pressure and prevent trap siphonage.\u003c\/p\u003e ✅ 500 DFU rating for venting DWV up to 4 in (76-102 mm)\u003cbr\u003e\n✅ Opens\/closes as needed by the plumbing system (secondary vent)\u003cbr\u003e\n✅ 3-4 in (76-102 mm) vent compatibility with 160 branch\u003cbr\u003e\n✅ PVC Schedule 40 straight vent adapter, black\/white finish\u003cbr\u003e\n✅ ASSE 1050\/1051 compliant, DIY friendly installation\u003cbr\u003e \u003cp\u003e💡 What is an air admittance valve used for in plumbing venting?\nA quick rundown helps explain how it works.\n- Provides a handy vent for DWV systems when roof vents aren't available\n- Opens to admit air and closes to prevent sewer gases\n- Compatible with PVC Schedule 40 straight vent adapters\n- Ensures ASSE 1050\/1051 compliance for safe operation\u003c\/p\u003e\n\u003c\/div\u003e","brand":"Amazon","offers":[{"title":"Default Title","offer_id":48719937536235,"sku":"VXB001GTVK62","price":99.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0662\/3268\/0683\/files\/61zB79AqziL.jpg?v=1780567352","url":"https:\/\/vxb.com\/products\/500-dfu-stack-air-admittance-valve-adapter-for-pvc","provider":"VXB Bearings","version":"1.0","type":"link"}