The 204 x 60mm Rectangular Ducting System is one of the most popular system sizes used in the market today. The low profile geometry of the system means that it can be easily concealed where space is restricted whilst still retaining the ability to handle high extraction rates. The 204 x 60mm Rectangular System is most commonly used for whole house ventilation and heat recovery installations whilst still remaining a good choice for single extract requirements such as Kitchens, Bathrooms and Utility rooms.