flow from an external gas source 103 through a filter 233 located in the grip frame 220 a passage 330 extends past the filter 233 and directs the gas into a pressure regulator which regulates the pressure by means of a spring and piston combination which has its operating pressure determined by the preset on the spring 723 created by pressure adjusting screw 231 the regulated gas is the directed to a transfer valve assembly fig6 a which controls the flow of gas to storage chamber 307 the grip frame 220 houses a regulator assembly fig7 a the regulator assembly as shown in fig7 a consists of a regulator input assembly as shown in fig7 b a regulator heart assembly as shown in fig7 c and a regulator output assembly as shown in fig7 d an exploded view of the entire regulator fig7 a is shown in fig7 e a regulator input assembly as shown in fig7 b is located in cavity 328 of the grip frame 220 fig7 b includes of a regulator input housing 714 with a passage from the input to the output the output passage is a gland 703 with radial flow passages which supports a regulator input seal 716 an input shaft 713 sits within housing.