The Spiralmate round duct connection system has been tested with up to 18-in. wg positive pressure and down to 10-in. wg negative pressure and suffered virtually no leakage. This increases your system's performance while reducing your liability and installation time. A patented flange connection system uses no external sealant, resulting in a clean, professional appearance with reduced labor time and cost.
Ductmate; 800/245-3188; www.ductmate.com.