A 75mm centrifugal fan is a small squirrel-cage fan. Centrifugal fans utilize a rotating impeller to draw air in parallel to the shaft and discharge it perpendicular to the shaft.

Applications
The compact size, airflow capacity make 75mm x 25mm blower fan is widely used to provide localized cooling and airflow in electronics, instruments, appliances and other devices, especially where compact size is critical.
Cooling Electronic Enclosures
A key use is installing these small fans on panels or walls of electronics enclosures like modems, routers, PLCs, industrial computers, switches and more. The centrifugal fan efficiently exchanges interior hot air for cooler ambient air to lower internal temperatures. This prevents overheating of sensitive components in densely packed enclosures. The compact 75mm size allows fitting fans to remove heat even in cramped spaces.
Spot Cooling in Instruments
Various instruments incorporate small heat generating components that need focused cooling. Mounting a tiny 75mm centrifugal fan to blow air over specific spots efficiently removes localized heat without requiring extensive air channels. Air Circulation in Appliances
the fans improve hot air exhaust and maintain even temperatures across the appliance. Preventing hot spots improves safety and avoids damage to components. The 75mm size can fit unobtrusively even in tight appliance compartments. In addition to versatile uses, 75mm centrifugal blower fan provides other beneficial attributes: Compact size occupies minimal space while still providing substantial airflow. The small impeller diameter allows installation in tight spots impractical for larger fans. Low noise output, prevents disruption in occupied spaces. Energy efficient low wattage operation reduces power demands. Durable brushless motors and sleeve bearings support quiet reliable operation