The On Call Extra Blood Glucose Monitoring System offers user friendly features for easier diabetes management at competitive prices. The smart and powerful data management is compatible with the On Call Diabetes Management Software. Additionally, the On Call Extra is certified to be compliant with the new ISO 15197 2015. Enzyme: Glucose Oxidase (GOD). Operating Temp Range: 5 – 45ºC (41 – 113 °F ). Operating Humidity Range: 10 – 90%. Test Range: 0.6 – 33.3 mmol/L (10 – 600mg/dL). Memory Storage: Up to 500 records with date and time. Automatic Shutoff 2 minutes after last action or 5 sec after strip removal. Battery Life 500 measurements.