Charging Valve, Hose   r Complete assembly: charging valve, gauge, & hose. SV1, G2.5, H10 Charging Valve SV1 Charging & bleeder valves with steel manifold 1/4" hose & gauge ports. Charging valve thread size is .305-32 UNEF. Gauge G2.5 1/4" N.P.T. port. Hose H 10   1/4" N.P.T. port & fitting for 2000 P.S.I. nitrogen bottle.   In order to check the precharge, it is necessary to have a charging valve (model SV1) and a gauge (g2.5). A hose (H 10) is also necessary if additional nitrogen is required.