A pulse oximeter is a non-invasive device used to measure a patients oxygen saturation and heart rate. The OxyPlus 240ST+ is the top-end variant in Clarity Medicals pulse oximeter category of machines. The OxyPlus 240ST+ is equipped with Clarity Medicals proprietary motion tolerance and smart artifact rejection technology that rivals other brands in the world. Coupled with a lightweight design, full RGB TFT display, long battery life, and up to 8 hours of SpO2 and HR trend storage, the OxyPlus 240ST+ is perfect for all your portable pulse oximetry needs.