Bostik 40-113 High Velocity Solvented Duct Sealant is a quick-setting, solvented, synthetic rubber based product, formulated for sealing longitudinal and flange joints in high velocity air conditioning and ventilation systems.
It provides a tough, resilient air-tight seal which prevents loss of internal pressure from the duct. It's both waterproof and flame retardant and has excellent adhesion to metal surfaces.