The Altair louvre system is used (from Breezway, Australia) which is available in both 102mm (4 inch) or 152mm (6 inch) wide glass, aluminium or timber blades. 

These comply with weatherproofing requirements up to high wind zones when used together with the louvre weather bar system at the sill. A fixed louvre system is also available for ventilating plant rooms and similar areas. A weather bar system at head and sill is available to ensure adequate weatherproofing in high wind zones.