facelake ® fl400p pulse oximeter with carrying case, batteries, neck/wrist cord - pink facelake the facelake fl400 pink finger pulse oximeter is a lightweight, portable device used for measuring both heart rate and blood oxygen levels or spo2. simply place your finger inside the sensor and have these measurements instantly displayed on a large led screen. features a battery-saving automatic power off function. we stand by our products with excellent customer service and a one-year warranty. note: this product is intended for sports and/or aviation use only and is not a medical device.