Our employee owned company is a professional manufacturer of "Gearless Diaphragm Pressure Gauges". We have world wide patents in the USA Germany, the U. K. , Japan & Taiwan. All our gauges are Durable, Shock Proof, sudden pressures endurable & different from the traditional bourbon tube or gears. All of our diaphragm gauges-meet ANSI B4. 01 1-1974 grade b requirements which means errors do not exceed 2% of span at any point between 25% and 75% of its span.