A pulse oximeter is a small, lightweight device used to monitor the amount of oxygen carried in the bodySp02 (Blood Oxygen Saturation) Measurement Range: 0–100%, Display Range: 0-99%PR (Pulse Rate) Measurement Range: 25-250 bpm, Resolution: 1 bpm, Accuracy: +- 3 bpmPI (Perfusion Index) Low perfusion up to 0.075%Results in 8 secondsIP22 Water and Dust resistantLightweight and compact 5.5 cm x 3cm x 3cmBattery operated, 2 x AAA (Not Included)* Colour may vary