Copper core pressure gauge of the Bourdon tube (copper) and stainless steel shell, copper alloy fittings, within the oil-filled shock. All stainless steel pressure gauge stainless steel Bourdon tube (imports) and stainless steel housing, stainless steel joint, within the oil-filled shock. Pressure gauge for pressure fluctuations in a larger range or to withstand the shock of the occasion, such as hydraulic systems, air compressors, drilling equipment, stamping equipment. The copper core pressure gauge for copper alloy corrosion media, such as hydraulic oil, gas, etc., generally used for low pressure conditions. The stainless steel pressure gauge can be used in corrosive media.