Data storage: In the product section of the sound level meter, you can refer to the English manual. The instrument automatically stores data every 2 seconds, and the stored value is the largest noise value in 2, which can last a year. Large Screen: Super large 9.6 LCD digital display with backlight makes reading more clear and visual in dark areas. Alarm function: You can easily set an alarm threshold. When the alarm is triggered, the measurement is stored and the value reached begins to flash for an adjustable period of 6 to 120 seconds and an audible signal sounds. When the measured value exceeds the alarm value, the sound beeps and locks the data flashing for 2 minutes. USB powered: By connecting a computer with a USB cable, you can download recordings, collect samples, and print maps, dates, etc. Wall Mount Type: With the hanging hole, it can be installed on the wall or free standing on the table. It can be used for families, factories, offices, hotels, hospitals, laboratories, theaters and audio systems, etc.