The RR range of in-line centrifugal fans, offer a very cost effective way, to ventilate using ducting up to 315 mm diameter ducting. These centrifugal fans combine the benefits high-pressure development with easy installation. Because they are a powerful these fans ensure that the system will move air even when the system resistance is much higher than expected. Thus the RR range is able to cope with moderate runs of flexible duct as spiral ducting. Installation is easy with a simple mounting arrangement (accessory MK4 foot) and easy to use connection to ducting using pipe clamps (BM pipe clamps an accessory).