Specifications: 

• Product Name: Sonmol digital peak flow meter
• Model: SMPF–2S
• Power Supply: Rechargeable
• Display: Segment LCD
• Test method: Pressure Sensor
• Measurement range: Volume: 0.5 ~ 8L    Flow Rate: 60L/min ~ 840L/min
• Accuracy: Volume: ±3% or ± 0.05L (whichever is greater)
• Flow Rate: ±10% or ±10L/min of reading (whichever is greater)
• Airflow resistance: 0.06 kPa/L/min
• Flow Rate Frequency response: ±12% or ±15L/min (whichever is greater)
• Working way: Continuous operation
• Operating environment: +10°C ~ +40°C; < 80% RH
• Operating atmospheric pressure: 700hPa ~ 1060hPa
• Transport, storage environment: -10°C ~ +55°C; <95% RH
• Transport, and storage of atmospheric pressure: 500Pa ~ 1060Pa
• Weight: 80g