Flexible hose

A flexible hose (1) for use as a refrigerant passageway in a vehicular refrigerating cycle has an inner hose (20) and an outer hose (10). The outer hose (10) covers the inner hose (20) with a space formed in a given distance. The outer hose (10) and the inner hose (20) are formed of resin having flexibility. A method of mounting a coupling assembly (40,40a,40b,40c) on a distal end of the flexible hose (1) is also disclosed.