conventional left handed threading 96 a for connection to the tank valve not shown in fig7 also includes suitable threading 96 b at the other end of the straight pipe section 96 c of connector 96 for providing the direct connection to the cylinder regulator not shown similarly to the embodiment of fig6 a schrader valve unit 98 is welded to the straight pipe section 96 c and includes a valve core 100 and a swivel nut 102 for actuating the schrader valve is also provided a flexible hose 104 connects nut 102 to a second female swivel nut 106 which differs from swivel nut 102 in that nut 106 does not include an actuating stem a further connector 108 including a male flare 108 a and a female adapter 108 b is used to connect hose 106 to a suitable gauge 110 referring to fig8 and 9 there is shown yet another embodiment of the invention this embodiment is similar to that of fig6 and 7 in that a valve connection is again made directly to the pipe connection to the tank valve rather than using a tee connector but in this embodiment a u201c saddle u201d valve unit indicated at 110 is used to make the direct connection as shown in fig8 a hole 112 is provided e g by drilling in a pipe connector 114 the latter may be a straight connector or a pigtail connector and includes an end connector 116 with.