Envirovent Silent 100mm 4" Ultra Quiet WC & Bathroom Extractor Fan with Intelligent Timer - SIL100ITThe Envirovent SIL100IT SILENT100 white silent IP45 axial extractor fan with intelligent overrun timer has a stylish design suitable for wall or ceiling mounting in toilets and bathrooms.The motor is mounted on silent elastic blocks, the fans deliver incredibly silent running and exceptional performance. Complies with all current building regulations.Fitted with pilot light, backdraught shutter, and airflow guide vanes as standard to improve pressure development and performance.Fitted with an intelligent overrun timer that calculates the amount of time to operate, depending on how long the fan has been running. It requires both a switched supply and a permanent life and earth.The SIL100IT is one of the more powerful bathroom fans, operating at 95m³/hr but is also one of the qu