This is the Yeah Racing 25x25x10mm Tornado High Speed Cooling Fan in Black color. This fan features dual ball bearings and is great for ESC's and other applications.
Bearing: Dual Ball Bearing
Operating: Voltage 5V ~ 7.2V
Start-up Voltage: 3V
Fan Speed: approx. 15000 R.P.M after 5~10 min. rotating.
Max Air Flow: 5.13CFM.