XAV-545 is a 5½-in. aluminum grille for buildings needing protection against violent weather. Able to withstand design loads of 300 psf produced by extreme wind phenomena, it is FEMA 320- or FEMA 361-rated for storm shelters and safe rooms as well as AMCA-certified. It is tested with impacts of 15-lb 2x4s traveling at 100 mph per ICC 500, making it compliant for windborne debris in all regions of the United States. It has a free area of 49 percent.