Asthmazine Fingertip Pulse Oximeter (SpO2): Heart Rate, Oxygen Saturation (Gray) Accommodates wide range of finger sizes - children to adult. Accurately determine your SpO2 (blood oxygen saturation levels) and pulse rate within seconds and display it conveniently on a large digital LED display. For sports enthusiasts, aviators or anyone who is interested in measuring their SpO2 (blood oxygen saturation level) and pulse rate. Buy with confidence: Sold by a Registered Respiratory Therapist. Manufactured with the same quality as those used by physicians, nurses, and respiratory therapists.