From the printed "24V DC Cooling Fan" parameter we can understand: Fan specifications for the 120 * 120 * 25mm; speed of 1200 rpm floating down about 10%; rated current of 0.1A minimum support 5V DC start; "24V DC Cooling Fan"maximum air volume 43.2CFM, noise test was 23.4 decibels, the running time of over 30,000 hours. After reading these parameters, then we open the packaging to find out, look at this "24V DC Cooling Fan" meets the packaging label mentioned characteristics of these products, whether as a qualified chassis fan is installed in the case played efficient cooling.