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Broan 639 Steel Wall Cap for 3-1/4 in. x 10 in. Duct, Black Enamel with Back-Draft Damper and Bird Screen
Regular price $54.54Orders start at $399 — combine any items to reach the minimum. Learn more
Broan 639 Steel Wall Cap for 3-1/4 in. x 10 in. Duct, Black Enamel with Back-Draft Damper and Bird Screen
The Broan 639 steel wall cap provides reliable through-wall ventilation for 3-1/4 in. x 10 in. duct. Its black enamel finish includes a built-in back-draft damper and a protective bird screen to keep pests out of the duct. Sold as one cap.
Key Features:
- Back-draft damper: Built-in damper helps stop outside air from entering when the fan is off.
- Bird screen: Protective screen prevents small pests and birds from entering the duct.
- Fits 3-1/4 x 10 duct: Designed for use with standard 3-1/4 in. x 10 in. duct.
- Black enamel finish: Steel construction with a black enamel exterior finish.
- Through-wall venting: Provides a reliable wall termination for ventilation systems.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | Broan |
| Sell unit | 1 wall cap |
| Product line | Broan 639 Wall Cap |
| Available colors | Black (1 variant listed) |
| Available sizes | 3-1/4 in. x 10 in. |
| Material | Steel |
| Color / finish | Black enamel |
| Dimensions | Fits 3-1/4 in. x 10 in. duct |
| Intended use | Wall ventilation termination for 3-1/4 in. x 10 in. duct |
| Included components | Back-draft damper, protective bird screen |
Fit and Compatibility:
Connects to 3-1/4 in. x 10 in. duct from Broan-NuTone and compatible ventilation fans and range hoods. Duct, fasteners and wall flashing are sold separately.
Frequently Asked Questions (FAQ):
Q: What duct size does this wall cap accept?
A: It is designed for use with 3-1/4 in. x 10 in. rectangular duct.
Q: Is a damper included?
A: Yes, a built-in back-draft damper is included to reduce outside air infiltration.
Q: Does it keep pests out?
A: Yes, a protective bird screen prevents small pests from entering the duct.
Q: What is it made of?
A: It is a steel wall cap with a black enamel finish.
Q: What else do I need to install it?
A: You will need matching 3-1/4 in. x 10 in. duct and mounting fasteners, which are sold separately.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
A wall cap is the termination point that protects the whole duct run, so choose one with a damper and screen like the 639 for exhaust fans venting through an exterior wall. Keep the duct run short and sealed, and orient the cap so the damper swings freely. Verify the cap opening matches your fan's 3-1/4 x 10 outlet before ordering.
Seal and secure all duct joints so exhaust gases and moisture vent fully outside and never into wall cavities.
Add the Broan 639 steel wall cap to your 3-1/4 in. x 10 in. duct system for dependable wall venting.
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