Range: -2000mV – 2000mV Accuracy: +/– 1mV Max Pressure: 100 PSI Temperature Range: 1 − 99 °C Speed of Response: 95% in 1 second Lab grade probes are designed to give the highest accuracy readings possible. The probes chemically inert body lets you expose it to fluorinated compounds and other powerful oxidizers or reducers that would normally destroy an ORP probe of lesser quality. The Atlas Scientific lab-grade ORP probe delivers reliable readings in whatever bizarre chemical you have made.