A coupling assembly for connecting adjacent ends of conduits, primarily used for aircraft fuel lines having redundant locking features is provided. This coupling can be manipulated with one hand and includes a central tine and laterally spaced locking tines which engage a mating channel for locking the coupling in secured relationship. Indicia is provided across the locking tines which is not visible when the coupling assembly is completely and securely closed. The coupling assembly can be manipulated with one hand and has viewing ports to be sure that all parts are in place. Also, the tines and guide members are configured to create a force between the two with a longitudinal component tending to open the assembly.