MD300C9211 is a very important and common device to check oxygen saturation (SpO2) and pulse rate. As a small, compact, simple, reliable and durable physiological monitoring device, Fingertip pulse oximeter is widely applied in clinic, hospital, social medical organization, first aid and homecare etc. Accurate Measurement Professional Guarantee 1. 1.12 OLED display SpO2, PR, and Pulse bar; 2. Level 1-7 adjustable brightness; 4 display modes; 3. Low power consumption; automatically power off ; 4. Special battery cover for more durability; 5. 2 AAA alkaline batteries; 6. Suitable for adult and pediatrics; 7. Optional sensors for different users;