The kit of the present invention is for use in the refilling within a survival unit of a gaseous supply tank through a filler valve having a threaded stem adjacent the free end thereof and a gripping surface on the filler valve. The gas is generally oxygen although other gas may be supplied. The kit includes an adapter to provide coupling relationship with the threaded stem of the filler valve so as to permit a flow of oxygen into the supply tank such that refilling thereof may take place without removal of the supply tank from the survival kit. The adapter includes an elongated member with an aperture extending therethrough and is adapted to mate with the filler valve in sealing engagement therewith so as to permit gas flowing through the aperture to enter the filler valve. The adapter further includes a holder with a bore extending axially therethrough and the elongated member extends axially through the aperture. A gripping section is provided on the adapter so as to obtain a coupling to the threaded stem such that rotation of the holder by means of the gripping section obtains abutting sealing engagement between the member and the filler valve. A wrench adapted to be used in conjunction with the adapter is provided as part of the kit. The wrench includes a socket for enclosing the gripping surface to provide retention of the filler valve in fixed position as the member is releasably coupled to the filler valve.