Feature: 1. One button operation, optical sensor technology, 10 second fast measurement. 2. Clear OLED display, four directions, convenient reading effect. 3. Clearly displays blood oxygen and heart rate with high accuracy. 4. Automatic shutdown in 8 seconds, energy saving and environmental protection. When the alarm value is reached, the number displayed on the screen flashes. 5. With a lanyard, it can be portable for family or traveling. Specification: Color: blue and white Material: ABS Display Type: OLED Display SpO2 measurement range: 70% -90% SpO2 Accuracy: ± 2% at 80% -99%, ± 3% at 70% -79% SpO2 resolution: ± 1% PR measurement range: 30 BPM-240 BPM PR accuracy: ± 1 BPM Alarm function: flashing numbers (SpO2> 100, SpO2 <90) (PR> 130, PR ＜ 60) Battery: 2 x 1.5V AAA batteries (not included) Working current: 2.5mA Working conditions: 5 ℃ -40 ℃, relative humidity 15% -80%, 70kPa-106kPa Product size: 55 * 30 * 32mm/2.2 * 1.3 * 1.2in Product weight: 26g/0.9oz Packing size: 8 * 6.7 * 4.7cm/3.1 * 2.6 * 1.9in Package Weight: 43g/1.5oz Package included: 1 * Finger Pulse Meter (Button color random) 1 * Lanyard 1 * User Manual (English) . Package List: 1 x Finger Pulse Meter (Button color random) 1 x Lanyard 1 x User Manual (English)