General Instruments vacuum gauge Model BSPG-P is designed for reliable panel-mounted vacuum indication in demanding industrial service. This lower back mount version uses a 4" / 100 mm dial, 1/2" Male NPT process connection and SS front flange for secure panel installation. Stainless Steel Made, with shatterproof glass window, SS316 wetted parts and a dry case prepared for filling where vibration or dynamic pressure conditions require liquid filling. Measuring range is -760...0 mmHg with 2nd scale bar, accuracy class is Class 1.0, and the process gauge design is suitable for pump skids, suction lines, compressor systems and general process duties.