The Derale 19917 is a 17 inch high performance flex fan for belt-driven engine cooling. Its aluminum flexible blades, finished in blue, flatten out as engine rpm rises to reduce the power the fan draws at speed while still moving strong airflow at idle and low speeds. The fan uses a black hub and turns in the standard clockwise rotation used by most V-belt and serpentine water pump setups.
Specifications:
- Type: Belt-driven flex fan
- Diameter: 17"
- Blade material: Aluminum
- Blade color: Blue
- Blade style: Flexible (flex) blades
- Hub color: Black
- Rotation: Standard rotation (clockwise)
- Part number: 19917
FAQ
What size is the Derale 19917 flex fan?
It is 17 inches in diameter.
What are the blades made of?
They are aluminum flexible flex blades finished in blue.
Which rotation is this fan?
It is standard rotation, turning clockwise, for common belt-driven water pumps.
Why choose a flex fan?
The flexible blades flatten at higher rpm to cut drag and noise while still cooling at idle and low speed.

