Description: This product fabricates high-quality fiberglass spiral ducts with speed and accuracy. Its four drive rollers and ¾-hp motor provide the necessary grip and power to quickly pull duct board ...

Among the more obvious reasons for the use of round duct on rooftops, such as preventing rain, snow and ice buildup, ease of wind passage is perhaps the most overlooked. PhenoliDuct, a new closed-cell ...