DL Wholesale Backdraft Damper - 4-in Duct - Galvanized Steel

Stop Reverse Airflow When Fans Shut Off - 4-in Duct

When an exhaust or intake fan stops, air can drift back through the ducting, carrying odors and outside air into your space. This backdraft damper closes against reverse flow, and its galvanized steel body and pre-installed rubber gasket on the exterior help keep the connection sealed.

This 4-in unit suits hobbyists and regular indoor growers running small-diameter ducting on a single fan, tent, or room exhaust line. Larger runs need a damper sized to match the duct.

Key Features & Benefits

• Backdraft prevention — blocks air from flowing backwards when the fan is off.
• Galvanized steel body — gives a rigid, durable housing for ducting.
• Pre-installed rubber gasket — sits on the exterior to support an airtight seal.
• Compact footprint — measures 4 in long, 4 in wide, and 5 in high, so it fits in tight duct runs.
• Light weight — ships at 0.8 lb, so it adds little load to the ducting.

Who Should Use DL Wholesale Backdraft Damper

Growers who want to hold in carbon dioxide supplementation and keep odors from flowing backwards through a fan line will find this useful. It suits indoor cultivation spaces with 4-in ducting.

About DL Wholesale Backdraft Damper

The DL Wholesale Backdraft Damper is a 4-in galvanized steel duct damper sold individually. It includes a rubber gasket pre-installed on the exterior and is designed to prevent reverse airflow when fans are shut off.

Frequently Asked Questions

Q: What does a backdraft damper do?
A: It lets air move in one direction through a duct and closes when the fan stops. This prevents air from flowing backwards into your space.

Q: Will it help keep odors contained?
A: It helps prevent odors from flowing backwards through the duct when the fan is off. It does not filter or treat air, so pair it with appropriate filtration if needed.

Q: Can it help retain CO2?
A: Yes. By blocking reverse airflow when fans are off, it helps keep supplemented CO2 from escaping through the duct line.

Q: What is the gasket for?
A: The rubber gasket is pre-installed on the exterior. It helps create an airtight seal where the damper meets the duct.

Q: What size duct does it fit?
A: It is listed as a 4-in damper. Check your duct diameter before ordering to confirm the fit.

Q: What is it made of?
A: The body is galvanized steel, which is a steel coated for corrosion resistance.