1.One way to four ways airflow.2.Neck sizes are 150*150mm,225*225mm,300*300mm,375*375mm,450*450mm.3.Designed for supply and exhaust of cooled and heated air.4.The centre core is removable for ease of access and maintenance.5.Anodized or powder coated. Normal colors are RAL 9016/9010.

aluminium Square Ceiling air Diffuser air grill