Feature 1HIGH SENSITIVITY: This smoke alarm, adopts maze sensing design, can sensitively detect smoke particles generated by fires, and trigger alarm in real time, provide protection for your home. 2HIGH VOLUME: The smoke fire alarm has a high volume alarm sound of about 85db, with strong penetration and can be heard by nearby people in a timely manner, thus taking corresponding protective measures. 3QUICK INSTALLATION: The smoke detector can be installed quickly and cleanly, which only takes a few minutes to install. Including installation accessories, you can choose any installation method you need. 4BATTERY REPLACEMENT REMINDER: This smoke detector will constantly monitor itself and quickly warn you of failure or low battery. Get uninterrupted 24 hour protection. 5TEST BUTTON AND FAULT REMINDER: With test silence button, when there is a low battery warning, pressing the test button can effectively mute for 10 hours. The smoke detector will give a beep sound while flashing red LED when fails.Item Type: Smoke DetectorMaterial: ABSBattery: 1.5V LR03 battery x 2 (shipped without battery)For Zigbee Standard: IEEE802.15.4Alarm Sound: 85dB/1mOperating Frequency: 2.405-2.480GHzInstallation Method: Ceiling installation .wang-edit-text{ font-family:'Arial' !important; } .wang-edit-text table { border-top: 1px solid #000; border-left: 1px solid #000; } .wang-edit-text table td, .wang-edit-text table th { border-bottom: 1px solid #000; border-right: 1px solid #000; padding: 3px 5px; } .wang-edit-text table th { text-align: center; }Package List1 x Smoke Detector2 x Screw2 x Anchor1 x User Manual1 x Pin