Wilkerson® by Dixon® Compact Regulator, High Pressure Self-Relieving Standard, series: R16, 1/2 in NPT/BSPP-G, 88 scfm, 0 to 250 psig, 32 to 150°F, Zinc. Wilkerson® by Dixon® R16-04RHG High Pressure Self-Relieving Standard Compact Regulator with GC240 Gauge, 1/2 in NPT/BSPP-G