Description: Display: OLED SpO2 Measurement range: 36~99% Resolution: ±1% Accuracy: ±2% (70%~99%), unspecified (<36%) Pulse Rate Measurement range: 30~250 bpm Resolution: ±1% Accuracy: ±1bpm or ±1% (select larger) Low Perfusion ≤0.4% Power 1.5V (AAA size) alkaline battery x 2(not included) Supply voltage: 2.6~3.6V Working Current: ≤30mA Automatic Power-off Automatically power off when no signal in the oximeter for more than 8 seconds