Product Information Name: Upper arm blood pressure monitorSize: 126mm(L)*100mm(W)*53mm(H)Blood Pressure: 20-280mmHgPulse Rate: 40-165 times/minStorage Memory: Double 99 group memoryPressurization: Automatic Pressurization ModeCuff Size: 22-32cm or 22-48cm for choosePower: AAAA batteries(not included)/usb chargingAdaptor: Included Euro/AU/US/UK adaptor according to countriesBacklight: 3 color backlightVoice Function:English Voice What is backlight mean? It means it has backlight always when measuring. In this way, you can see the screen clearly even on dark. And see more clearly on day time. Also, if your blood pressure is high, the screen show red. if your blood pressure is slight high, the screen show yellow. If your blood pressure is normal, the screen show green. Compared with No backlight model, it is more easier to see the result especially for elder people. What is English Voice mean? It means, it has live English voice during the whole measurement. It will tell us how to take measurement and the result. If you do not want the voice, it can also turn it off. Advantage 1; We have sell this product in China for more than 15 years and it is really great It is China famous brand, golden quality We have sell in Aliexpress for more than 7 years.2; We now upgrade the s We provide 3 color model with backlight and English voice .3; We also add big cuff 22-48cm option for those people who need large size cuff tonometer to watch their health. Health is really important for us And a tonometer will help a lot Give it to our loved ones