The PEF4020 XF100T Adjustable Over-run Timer Fan from 1-20 minutes  has a slim looking design and is made for wall, ceiling and window mounting. Quiet and efficient, it has an extraction rate of 85m3 /hr, 23 litres per second.The unit is made from high ABS thermoplastics for strength and durability and easy cleaning. A single phase induction motor with pre-oiled bearings provides power. It has been designed to comply with building regulations on ventilation and is perfect for use in bathrooms and toilets.