RD-DS 181 Acrylic duct sealant is a gray water based duct sealant used in medium and high pressure duct systems. It is a special formulation which is non-flammable and provides permanent flexibility, excellent water resistance and superior sealing strength. Use it to seal metal to metal joints to prevent air leaks in medium and high pressure systems of spiral and rectangular ductwork for air-conditioning, refrigeration, ventilation and air distribution. RD-DS 181 may also be used to seal joints on run-outs of connecting metal flexible tubing.