DASCO’s perforated ceiling diffuser is a multi-vane type featuring a fully and easily removable perforated face. The face plate is characterized by 4 mm diameter holes on 6 mm pitches, providing a 40% free area. Available with either square or round necks, the diffuser can be supplied in 1, 2, 3, and 4-way airflow patterns to meet all air distribution requirements. An optional opposed blade damper section (for supply diffusers only) can be fixed to the outer frame and is lever-operated from the face; a key-operated version is also available upon request. The damper blades are separated from their frame by nylon bushings to eliminate corrosion and vibration. These perforated diffusers are available in both square and rectangular patterns for supply and return air applications, with the return-air versions supplied without a damper as standard.