Manrose MF100S 100mm In-Line Mixed Flow Extractor Fan The Manrose 4 inch inline fan provides a high extraction rate whilst keeping noise to a minimum. The mixed flow created by the twin blades enables the fan to pull more air than a conventional extractor fan making it ideal for use in bathrooms and other areas of high humidity. 3 Speed Settings - MF100S benefits from 3 speed settings which can be set via dip-switch at installation. This allows the fan to operate at an appropriate rate for user requirements.