shaped head portion 62a and a screw portion and is screwed in a circular depression 64a formed in a second movable member 3a corresponding to the first movable member 3 in contrast to the first connector 1 in the second connector 2 the large diameter portion 38a of the valve body 4a has no nut 44 and instead it increases its diameter further at the corresponding portion to enlarge the effective area of its butting face 68 against the annular sealing member 34 of the first connector 1 since the first and second connectors of this device include similar poppet valves respectively similar operations are effected in both connectors at the time of connection and disconnection of the piping and not only the passageway 8 of the first connector but also the passageway 10 of the second connector are closed at the time of disconnection accordingly the fluid remaining in the utilization device after disconnection is prevented from leakage this is advantageous when the fluid used is a fluid other than air such as oil as described above the design of the second connector is optional and has no direct connection to this invention it should be noted that the above embodiments have been presented for illustrative purpose only and do not mean any limitation of the invention it is a matter of course that various modifications and changes can be made on these embodiments without leaving the spirit and scope of the invention as defined in the.