Display Type: LED Max SpO2 Display Value: 100% SpO2 Measurement Accuracy: +/-2% SpO2 Resolution: 1% PR Display Range: 0-250bpm PR Measurement Accuracy: +/-2bpm PR Resolution: 1bpm Power Requirements: 2 AAA Batteries Your SpO2 and Pulse Rate at Your Fingertips The 500DL Pro Series Fingertip Pulse Oximeter is the only LED pulse oximeter on the market that can display SpO2 value up to 100%. It is covered with high quality light absorbing material, preventing interference from the environment, making it accurate and reliable under almost any condition. Manufactured based on FDA and CE requirements, the 500DL Pro series can now accurately determine your SpO2 (Blood Oxygen Saturation Levels), Pulse Rate and Pulse Strength quickly and reliably. No Deviation of Oxyhemoglobin value measured in natural lighting indoor condition and that measured in dark room. Measurement Performance: Oxyhemoglobin and Pulse value can be shown accurately when pulse-filling rate is 0.2%.