Contec SP80B Handheld Rechargeable Bluetooth Spirometer Lung Monitor
The data can be transmitted by Bluetooth or USB cable. User Manual. Working current: 200 mA. Flow accuracy: ± 5 % or ± 0.2 L/s (whichever is greater). Flow range: 0 L/s ~16 L/s. Display mode: 2.8" LCD.