Principle of the CMS60D-Vet Pulse scanner is as follows: Photoelectric Oxyhemoglobin Inspection Technology is adopted in accordance with Capacity Pulse Scanning & Recording Technology,The Veterinary Pulse tester can be used in measuring the pulse oxygen saturation and pulse rate through animal's tongue or ear and so on.The product is suitable for being used in family,pet hospital and etc. (It is recommended to use the device when the animal is still.Display Mode: 1.8" Color OLED display. This monitor is designed for sports and aviation use only, and is not a medical device.Please note:Only CONTEC is the direct manufacturer,and only we can offer you the best service.Thanks.