Features: 1.Pulse oximeter for sports has 2-direction display adjustable. 2. Reliable accuracy and durability. 3.Automatic shutdown when no signal. 4. Small size, light weight, easy to carry. 5.Low voltage indicator, real-time spot check. The sensor can get the best reading. If your PI is high, then your measurement is perfect and you can be confident in your measurement. Auto Power Off: Auto power off in 5 seconds when finger is not inserted Multi-functional: Digital can be used to accurately measure pulse rate and oxygen saturation levels Easy to read: SPO2, pulse and bar graphs are supported, and you can view the results very clearly on the OLED display Easy to use: Accurate and reliable, one-button operation, simply clip it to your finger and turn it on with the push of a button. Automatically turns off after 5 seconds when not in use Wide range of application: suitable for daily use. Widely used in family occasions, oxygen bar, fitness and so on Perfusion Index PI% is an advanced measure of signal strength Packing list: 2 x Display 2 x User Manual 12x Lanyard Required 2 x AAA batteries not included The sensor can get the best reading. If your PI is high, then your measurement is perfect and you can be confident in your measurement. Auto Power Off: Auto power off in 5 seconds when finger is not inserted Multi-functional: Digital can be used to accurately measure pulse rate and oxygen saturation levels Easy to read: SPO2, pulse and bar graphs are supported, and you can view the results very clearly on the OLED display Easy to use: Accurate and reliable, one-button operation, simply clip it to your finger and turn it on with the push of a button. Automatically turns off after 5 seconds when not in use