LIQUID/GLYCERIN FILLED GAUGES ARE SPECIFICALLY DESIGNED FOR APPLICATIONS WHERE VIBRATION AND PULSATION IS PRESENT 10 PACK OF LOWER MOUNT GLYCERIN FILLED VACUUM PRESSURE GAUGE, FACE/DIAL SIZE 2-1/2", 1/4" MALE NPT CONNECTION, 30" Hg VAC/15 PSI, (-30 - 15 PSI), RANGE PLEASE NOTE: 1/4" MALE NPT MEASURES 0.540" OUTSIDE THREAD DIAMETER. THESE ARE INDUSTRIAL GAUGES AND NOT DEEMED LEAD FREE. DO NOT USE WITH POTABLE WATER APPLICATIONS. GLYCERIN FILLED, POLYCARBONATE LENS, STAINLESS STEEL CASE & BEZEL, COPPER ALLOY INTERNALS, BLACK ALUMINUM POINTER, DESIGN MEETS OR EXCEEDS ASME B40.100 PRESSURE GAUGE STANDARD 3/2/3% ACCURACY, AMBIENT TEMPERATURE -50f TO 160f, SEE ADDITIONAL PICS FOR DIMENSIONAL DATA, PSI/BAR THESE ARE INDUSTRIAL GAUGES AND NOT DEEMED LEAD FREE. DO NOT USE WITH POTABLE WATER APPLICATIONS. APPLICATIONS INCLUDE OIL, WATER, AIR, COMPRESSOR, HYDRAULICS, HVAC, GASEOUS & LIQUID MEDIA THAT ARE NOT HIGHLY VISCOUS OR CRYSTALLIZING AND NOT CORROSIVE OR OXIDIZING TO COPPER ALLOY PARTS. INDUSTRIAL GAUGE SPECIFICATIONS_ LENS: PLASTIC, WETTED PARTS: COPPER ALLOY, CASE: STEEL, POINTER: BLACK ALUMINUM, ASME B40.1 GRADE B