A visit to the doctor may sometimes cause anxiety and nervousness, which may lead to negative and inaccurate readings. Keeping track can help you and your doctor monitor and see the effects of treatment over time. Save electricity, more extend battery life. Support USB charging and battery installation. Easy to carry, suitable for family and travel use. Monitor your health at any time - LARGE SCREEN DISPLAY function, clear screen, screen tilt angle of 30, easy to read, compare, record blood pressure values.