Forbes Marshall is one of the pioneers in the manufacture of Gas Filled Dial Thermometers, Bi-metal Thermometers, Pressure Gauges, Vacuum Gauges, Compound Gauges, Capsule Gauges, Differential Pressure Gauges, IBR approved Gauges, Comparison Test Pumps, Combustion Test Kits, Fyrite Kit - CO2 & O2,Temperature Recorders and Pressure Recorders (Mechanical / Electronics).