Wi-Fi connection, easy to install, no need to consider line problems, safe and convenient. The alarm's LED indicator lights up in red and strobes, and an audible alarm is sent to the Tuya or smart home APP via the WiFi network. After the air is fresh and clean, it will stop the alarm and return to the low-power state of normal monitoring. Mute function: During the alarm process, press the test button to mute the device, leaving only the flashing led light. When the battery is low, the alarm will sound an alarm to remind you to replace the battery in time.