2-1/2" Oil Filled Vacuum Pressure Gauge - Stainless Steel Case, Brass, 1/4" NPT, Lower Mount Connection, 30HG/100PSI Professional quality & durability Stainless steel case, Copper alloy wetted parts 1/4" Lower mount connection Broad applications - water, oil, air and more -4F to +140F (-20C to +60C)