Square air diffuser

This product description: Surface Finish: white powder coating, oven baked finished products.Airflow attached flat delivery, suitable for office air supply system in public places Detachable inner core and the frame for easy installation, commissioning and cleaning Air supply valve with people supporting the use of the word, you can control the regional distribution of air, return air filter plus This product has three dimensions, namely: external diameter size (face size), neck size (ceiling opening size), the throat size (the wind pipe interface size) The formula is: the throat size of area = (A +125 mm) * (B +125 mm) The neck size of an area = (A +60 mm) * (B +60 mm)