The RegO®-LOK™ is designed for installation on the RegO® T9450 and T9460 Series liquid cylinder valves to deter and prevent the removal of the CGA fitting from the valve. The RegO®-LOK™ retains standard CGA outlet connection so unauthorized persons do not remove the fitting. By use of a special one-way bolt, the RegO®-LOK™ is secured to the valve. The RegO®-LOK™ installs in a few minutes with the use of screwdrivers, without valve disassembly, brazing, welding, or drilling. The RegO®-LOK™ deters and prevents fitting removal by gas customers, however allows the replacement of fittings by authorized gas supplier plant personnel.