How to Use the Product?\r\n\r\n 1. Set the unit (This product is preseted before, so you can use it directly without resetting. If you want to change the testing unit, you can refer to the chart at the end of the user manual.)\r\n 2. Set the alarm triggering values\r\n 3. Make a Test\r\n 1) Long press power button for 2 seconds, and the product will turn on after a “di” sound.\r\n 2)At this moment, the screen will display “WAIT” with 15 seconds countdown, which means the product goes into the preheating mode. The preheating will be completed after the countdown ends.\r\n 3)After preheating, the screen will display “START” to prompt user to blow. Make the blowing test within 10 s after the START prompt showed on screen (Blowing in one breath for 4-5 s).