This is a Delta Electronics DC12V 0.35A 40x40x15mm 4-Pin DC Brushless Fan. Its model number is AFB0412SHB.

Specifications:

• Manufacturer: Delta Electronics
• Part Number: AFB0412SHB
• Operating Supply Voltage: 12 VDC
• Airflow: 14.8 CFM (0.42 m3/min)
• Speed: 11000 RPM
• Bearing Type: Ball
• Noise: 41.5 dBA
• Power Rating: 3 W
• Current Type: DC
• Pressure Type:15 mmAq
• Termination Style: 4 pin plug
  
• Housing Material: Plastic
  
• Height: 40 mm
• Width: 40 mm
• Depth: 15 mm
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