lpow pulse oximeter fingertip, blood oxygen saturation monitor for pulse rate, heart rate monitor and spo2 levels with oled screen display batteries and lanyard included ankovo features: 1. this oxygen meter is small in volumes, light in weight and easy to carry. 2. one button operation and easy to use. 3.large led display and low in power consumption. 4.accurate and reliable. 5.automatically turning into sleep mode within 8seconds after there is no signal. technical specification: ▴parameters : spo2, pr,pi ▴spo2 measure range : 35% - 100% ▴resolution : ±1% ▴accuracy : 70%-100%:±3, <70%:unspecified ▴pulse rate range : 30-250bpm ▴accuracy : ±1bpm perfusion index: 0.1% - 10% ▴resolution : ±1bpm ▴power requirements:2×1.5v aaa battery (rechargeable battery also available) ▴dimension: 62 ×34 ×31cm ▴weight: 50g(including the battery) includes: 11x lpow pulse oximeter 22×aaa batteries 31x lanyard 41x instruction manual note: this device is for sports and aviation use only.