Abstract: An improved readily attachable and detachable coupling for fluid conduits including a receptacle member having a passageway therethrough and having at least one notch formed in the external surface communicating with the passageway, the notch having a forward wall inclined at an acute angle to the member longitudinal axis and a rearward wall which is substantially perpendicular to the longitudinal axis, and a plug member of a diameter to be slideably received within the receptacle member passageway, the plug member having an enlarged external diameter portion spaced from the end, the receptacle member having a retention wire received thereon with a straight portion extending within the notch and with the wire extending less than the full circumference of the receptacle, the ends of the wire being spaced apart so that when the plug member is inserted into the receptacle passageway, the enlarged diameter portion can push past the retention wire, and a release collar received on receptacle and having a portion w