Elina HDF4012L-05LB , 40 x 40 x 12 mm, 1.57 x 1.57 x 0.47 inches, 5 Volt Cooling Fan 40 x 40 x 12 mm, 1.57 x 1.57 x 0.47 inches, 5 Volt Cooling Fan Operating Voltage: 4.25 to 5.75 VDC Rated Current: 120 ma., Rated Input 0.65 watts Rated Speed: 4900 rpm Low Speed 5 VDC Fan