The cooling air specialist ebm-papst has developed the new CR 6300 N (counter rotating) for such cases. Here, two single fans connected by an intermediate piece work together to provide high efficiency with minimal space requirements. The operating noise is up to 4 dB(A) lower than for high-revving single fans. The CR 6300 N can achieve a flow rate of up to 1145 m³/h and a counter pressure of up to 1858 Pa. The counter rotating team consists of two adjustable fans of the CR 6300 N series. These rotate together in opposite directions. The rear fan can thus efficiently convert the residual twist of the front fan into output; the efficiency is greater than individual solutions. Both fans are connected by a 30-mm-wide intermediate ring, which varies depending on the application. With both 51-mm-deep fans, the total unit has a length of only about 132 mm. The fan housing made of die-cast aluminum and the wheels made of glass-fiber-reinforced PA are aerodynamically optimized for each respective direction and each weigh only 875 g. The fans and ring can be purchased as a single unit or as a kit. With 48 VDC operating voltage, the CR 6300 N is well-suited for all applications that require a particularly space-saving cooling fan and/or powerful yet highly efficient air delivery.