4" PVC Extendable Backwater Valve 4" -BWV4-Ext

Introducing the BWV4-Ext, a 4-inch PVC Extendable Backwater Valve from Mainline Backflow. This extendable, normally closed gravity-flow valve is designed for PVC-DWV drainage systems, delivering reliable protection against sewer backflow while adapting to tight or awkward installations. Its white finish and hub-to-hub compatibility ensure a clean, professional look and easy integration with standard piping.

Benefits

• Provides dependable backflow protection by automatically closing to prevent reverse flow.
• Extendable length offers flexible installation in limited or irregular spaces.
• Normally closed gravity-flow operation delivers passive protection with no additional actuation.
• Durable PVC-DWV construction resists corrosion and harsh wastewater exposure.
• Hub-to-hub connections simplify alignment and compatibility with existing piping.
• Clean white finish maintains a discreet appearance in finished installations.

Key features

• Model: BWV4-Ext
• Size: 4 inches (4") diameter
• Material: PVC-DWV
• Operation: Normally closed, gravity-flow
• Extendable length: Yes, adaptable to installation needs
• Connections: Hub x hub
• Finish: White
• Manufacturer: Mainline Backflow
• Application: Backwater valve for drainage/sewer protection