Can anyone tell me how to turn off the gas from this type of valve, when u remove the screw cover there is another screw inside, anti-clock wise removes the screw and gas comes out, but when I screw it clock-wise it feels like it goes down forever and I'm scared incase it drops inside the fitting, the back of the cover has a slot that locates into the scre head. Any help much appreciated.
[/img]
[/img]