
White Rodgers 21M51U-843 Universal 2-Stage Furnace Control Kit
Part/SKU: 21M51U-843
| Weight | 6 lbs |
|---|---|
| Condition | New |
| Manufacturer Part Number | 18X16-311P |
$27.74
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This 18″x16″ tapered HVAC duct reducer is designed to transition from 18-inch round duct to 16-inch round ductfor commercial HVAC, ventilation, and exhaust duct systems.
Manufactured from durable galvanized steel, this reducer offers excellent corrosion resistance and long-lasting performance in demanding mechanical installations.
This model is labeled NO CRIMP, meaning the ends are straight and ideal for installers who prefer custom fastening using sheet metal screws, clamps, duct sealant, or HVAC foil tape.
The tapered reducer design helps maintain airflow efficiency by reducing turbulence and pressure loss compared to straight reducers.
Size: 18″ to 16″ round duct transition
Heavy-duty galvanized steel construction
Tapered design for smoother airflow
No Crimp ends for flexible installation
Ideal for commercial HVAC ductwork, ventilation, and exhaust
Commercial HVAC duct transitions
Industrial ventilation systems
Large exhaust duct reductions
Retrofit duct size conversions
Compatible with standard round ductwork.
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