Here you will find all Grada perforated ceiling diffusers with top entry spigot and adjustable supply air! These diffusers are suitable for a 600x600 suspended ceiling. Via the four separate dampers, the supply air with this diffuser can be adjusted manually! The ceiling diffusers have a top entry spigot, available in different diameters. This means that a diffuser is available for all ducts. The perforated ceiling diffusers have a panel perforation of approximately 51% and are made of steel. Still looking for another diffuser? Then take a look at our full range of ventilation grilles!