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🔄 Upgrade your airflow game with seamless duct transitions!
The Deflecto Duct Increaser and Reducer (IRB43) is a lightweight, durable plastic adapter designed to connect 4-inch ducts to 3-inch ducts effortlessly. Made from heat-resistant polypropylene with a melting point of 325°C, it ensures safe and reliable performance in bathroom fan and dryer exhaust installations. Its slip-on design allows for quick setup, making it an essential upgrade for efficient home ventilation.
| ASIN | B005XU3QCQ |
| ASIN | B005XU3QCQ |
| Batteries Included? | No |
| Batteries Required? | No |
| Best Sellers Rank | #45,955 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #50 in Heating & Cooling Ducting Products |
| Color | White |
| Customer Reviews | 4.3 4.3 out of 5 stars (733) |
| Customer reviews | 4.3 4.3 out of 5 stars (733) |
| Date First Available | 17 June 2010 |
| Date First Available | 17 June 2010 |
| Department | Electronics |
| Included components | Deflecto Duct Plastic Increaser and Reducer, 4" to a 3", (IRB43) |
| Is Discontinued By Manufacturer | No |
| Item Package Quantity | 1 |
| Item Weight | 22.7 g |
| Item model number | IRB43 |
| Item model number | IRB43 |
| Manufacturer | Deflecto |
| Manufacturer | Deflecto |
| Material | Plastic |
| Number Of Pieces | 1 |
| Part number | DEFIRB43 |
| Product Dimensions | 10.16 x 8.64 x 10.16 cm; 22.68 g |
| Product Dimensions | 10.16 x 8.64 x 10.16 cm; 22.68 g |
| Special Features | Lightweight |
D**.
Worked perfectly for the larger air pump I added to my wecreat 45w pro laser
P**R
I used mine to go from 3” to 4” (expander) rather than reducer and it did the job I wanted.
A**I
As others have said the 4 inch side is the same size as the 4" outlet duct on newer bathroom vent fans BUT I used a hot glue gun to essentially "weld" the two plastic pieces together. To assure a strong connection I wrapped the joint afterward with silicone self adhesive tape. I imagine duct tape would also work. The existing 3" flexible duct was a snug fit, but with a little effort it went over the 3" side of the reducer. I considered using a galvanized steel 3x4 duct adapter (Home Depot, Menards) but because of all the shower moisture being vented out I was concerned with the piece rusting over time. The plastic reducer was cheaper and will be rust-free.
A**R
Product worked as advertised.
K**N
I didn't find this suitable for use on ducting on a bathroom exhaust fan, as the external diameter was too large. I ended up getting a galvanised reducer, instead, which was perfect.
Trustpilot
2 months ago
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