Hoffman A4AXFN, 4" Fan, designed for use in enclosures where space is limited and reliable cooling is required.

Compact Cooling Fans are ideal for applications where enclosure space is limited and quiet, reliable cooling is required. Engineered for 50,000 hours of continuous operation without lubrication or service.
Installation
Can be installed on any surface of an enclosure. With the addition of accessory fan brackets, Compact Cooling Fans can also be installed in any position inside the enclosure for spot cooling or air circulation.
Maximum operating temperature is 158 F (70 C)
4-in. fan is thermally protected and uses permanently lubricated ball bearings
6- and 10-in. fans have ball-bearing construction and split capacitor motors
Split-capacitor motors are thermally protected to avoid premature failure
Dynamically balanced impellers molded from polycarbonate material
One finger guard is furnished (additional finger guards are available)
All mounting hardware is provided
Fan bracket and additional finger guards must be purchased separately
240 and 560 CFM fans have ball bearing construction and split capacitor motors
Fans have leadwires with ends stripped 1/2-in. (12-mm) or 6-ft. (1.8-m) cord with polarized plug for power connections