Features: 130db Alarm & App-Alerts: Built-in vibration sensor can detect slight vibration of door and window, and will start 130dB alarm sound and you will receive an alarm notification via application at the same timing. WiFi Window Door Security Alarm & Adjustable Sensitivity: Wireless door window sensor works with your 2.4GHz WiFi. No screws required. Adjustable sensitivity allows you to set according to your needs. Easy Installation: No wiring needed and No Need to use complicated tools when installation, and just use 3M glues (attached-in-package) to stick the alarm on any door, and also window or glass. Wide Applicability: It can also be used as doorstop alarm, pool door alarm, garage door alarm or sliding door alarm. And its perfect for any door and window in your home, garage, office, car, dorm room. Low Battery Warning: Low power consumption, and requires AAAx2pcs batteries (not included). When the battery is running low, LED will flash and the application will remind you to replace the battery in timing. Specifications: Material: ABS Color: Black/White Package Weight: approx.53g Size: approx.74x74x13mm/2.91x2.91x0.51in (More Size Detail, Please See Photo.) Package Includes: 1Pc x Wireless Door Vibration Sensor Alarm note: Please allow 1-3mm error due to manual measurement. Please make sure you do not mind before you bid. Due to the differences between different monitors, the picture may not reflect the actual color of the item. Thanks!