OMNI Health Navi Easy Check with Your Fingertip 4 Functions Helpful for Wellness (Blood Oxygen Saturation, Pulse Rate, Perfusion Index (PI), Pulse Strength) This is a brand new item, just arrived. Opened to check the contents, and operation has been confirmed with batteries inserted. Model Number: OMHC-CNPM001M Size: Approximately 5.5 x 3.0 x 2.8 cm Weight: Approximately 25g Materials: ABS resin, Silicone rubber Rated Voltage: DC3V Batteries Used: 2 AAA alkaline batteries (sold separately) Measurement Range Blood Oxygen Saturation (SpO2): 50-100% Measurement Range Pulse Rate: 30-250bpm Measurement Range Perfusion Index (PI): 2.5-20% Country of Manufacture: China