Stay healthy with iO2. Dual colour, OLED display, is quick and easy to spot-check of pulse rate and oxygen saturation. Specifications: 1. Display type: OLED display 2. SpO2: - Measurement range: 70-100% - Accuracy: ±2 at 70-100% - SpO2 alarm limit: high: 100, Low: 90 3. Pulse rate: Measurement range: 30-250 BPM Accuracy: ±2% BPM Pulse Intensity: Bargraph Indicator Pulse rate alarm limit: high: 120, low: 60 4. Power Requirements Two AAA alkaline batteries Power consumption: Less than 60 mA Low power indication Battery life: Up to 15 hours 5. Dimensions: 71.99(L) *36.84(W)*35.8(H) mm Weight: 42g (without battery) 6. Environment Requirements: Operation temperature:0 - 45° Storage temperature: -10 to 50°