An FRP cowl is a hood-shaped covering that fits over a chimney stack or ventilation discharge. It's used at the end of ducting systems when air is discharged outside. The "U" bend of the cowl holds water and prevents foul gasses from passing back into the kitchen. FRP stands for Fiberglass Reinforced Polymer. It's one of the world's strongest and most durable materials. FRP is non-reactive, corrosion-resistant, and won't warp, rot, or decay from exposure to moisture. It's also highly corrosion resistant and weighs up to 75% less than steel but is equally strong.