Quality fan, part number AFB0812VH-F00. 

This is the 4-wire type, with red & black power supply wires, plus a yellow tachometer wire and blue PWM control wire. The blue & yellow wires can be left disconnected, if not required. 

Labelled as Delta AFB0812VH, but this is almost certainly a clone and should not be considered an original Delta electronics product.

Suitable for cooling RF or audio amplifiers or any project requiring a good airflow. 

Specs:

• Dual ball bearings for long life
• High output 42CFM airflow
• Sound level 38dBA
• 12V supply @0.41A
• 3600 RPM
• Size 80 x 80 x 25mm
• 30cm flying leads with 4-pin plug on the end.