Gauge Valve Include Gauge Union Bonnet Needle Valve with bleed plug and without bleed plug. Gauge union bonnet valve with one side drain and with bleed plug and hex head bleed valve. material Construction : SS. 304, SS. 306, Carbon Steel (CS) and Monel. Size : 1/2"and 3/4" with NPT, BSPT, male and female. Testing 1 100% tested at 6000 PSI.