The visible parts of the A/C system ducting are the air supply grilles covering the outlets which are usually wall-mounted near the ceiling and control the air distribution from the system (temperature range 0º up to 65ºC / 30 up to 140 ºF ). The air supply grilles A.B.S engineering Plastic consist of a row of adjustable louver blades in the front and a row of parallel blades in the back. In the front individual louvers are adjusted in each segment with a handle on the centre blade to adjust the air discharge angle in sideway direction. The back damper blades segment adjust the air discharge angle to up and down directions. Damper blades also control the air throw. Maximum airflow is obtained when blades are in straight position while a shorter throw is obtained when blades are in an inclined position. For a complete shut-off damper blades can be closed. For better distribution of the air we recommend to use our opposed blade dampers. The air supply grilles are made of non–toxic plastic ABS in standard glossy off-white color, preventing condensation, scratch and corrosion resistance, wipes clean, consistent color and wide range of colors availability. Sizes: double deflection supply grilles are built in a modular pattern and are supplied in 9 heights: 110, 150, 200, 220, 300, 330, 400, 440, 550 & 660 mm (4.5, 5.9, 7.9, 8.6, 11.8, 13, 15.7, 17, 21.5, 26” ).