Abstract: An apparatus for coupling and sealing tubes, comprising a flexible duct having a first and second end portions, each portion having an outwardly extending seal portion connected to a flat portion, which in turn is connected to an angled portion which connects to a flat portion having expanded diameter. The apparatus also comprises a sealing assembly comprising a split ring, a compression ring and an end cap subassembly which fits over the compression and split rings. The end cap subassembly comprises a pair of half-rings which are hinged together at one end and latched together using a closure mechanism at the other end. The split ring is mounted over the duct end seal after a tube with a bead is inserted inside the duct. A compression ring is fit over the split ring and the end cap subassembly is latched in place over the compression and split rings, thereby placing the duct seal portion under compressive pressure against the tube and maintaining it in place in a sealed relationship.