4312MV - 

These brushless DC fans automatically adjust their speed, depending on measured temperature! The internal circuitry adjusts the fan speed, using an externally connected temperature sensor (LZ370). This means at cooler temperatures, the fan runs at a quieter, lower speed.
Features:

UL Yellow Card E38324, CSA File 27697, VDE File 3072

Electronically Communicated External Rotor Motor

Fully Integrated Communication Electronics

Protected Against Reverse Polarity, Blocking and Overloading

Sintec Bearings

Fiberglass Reinforced PBT Plastic Housing

Fiberglass Reinforced PA Plastic Impeller

Mounting from Either Face Using Four 3.5 mm Holes

Air Exhaust Over Struts, Counterclockwise Rotation Looking at Rotor

Electrical Connection Via Two 28 AWG TR 64 12.2 In. (310 mm) Long Leads

0.96 Oz. (27.2 g)

70°C Maximum Ambient Temperature Rating

6000 RPM Operation