About This Item Specification Material: ABS Size: 7.5X6.5X3CM Wristband: 23CM Box: 9.5X9X7CM Parameters: Storage temperature: -20 ~ 50 Storage humidity: 15% ~ 90% Working temperature: 10 ~ 40 Operating humidity: 40% to 85% Display mode: LCD digital display Measurement method: pulse scanning / oscillometric Measuring range: hypertension / hypotension: 20mmHg ~ 280mmHg Pulse: (40 ~ 200) times / minute Accuracy: 3mmHg ( 0.4kPa) Pulse: within 3% of reading Voltage: 3V Package includes 1X blood pressure monitor 1X English manual Notice: - Please allow slight dimension difference due to manual measurement. - Please consider the actual sizes in the listing as the pictures are generally enlarged to show detail. - Due to different producing batches, product details might be a little different. If you minding the difference, please buy it carefully. - Due to the light and screen difference, the item's color may be slightly different from the pictures. Thanks for your understanding. Brand:Willstar It can measure the systolic and diastolic pressure and the pulse in seconds. With the adjustable cuff from 22 to 32 cm it is suitable for the most frequent arm measurements Easy to read: with a large LCD display, it measures blood pressure and heart rate quickly, and is easy to read Irregular heart rate indication: once it detects an irregular heartbeat, it will be indicated and alerted to this abnormal signal instantly The large size of the bracelet fits the circumferences of the arm from 22 to 32 cm (8.7 "to 12.6") The blood pressure monitor is powered by 4 AA batteries (not included), or with an AC adapter (not included). Practical to use and carry anywhere if used with AA batteries