Knightsbridge Screwless 10AX 3 Pole Fan Isolator Switch - Matt Black with Chrome Rocker. This switch is ideal for providing a safe and simple method of isolating fan units in en-suite bathrooms, family bathrooms, utility rooms, store rooms etc. Often the fan unit will be wired into the lighting circuit for convenience and efficiency. With this kind of installation, there is often a need to leave the lighting circuit live whilst isolating the fan for maintenance. Suitable for use in various domestic settings. Manufacturer: Knightsbridge.