Feature: 1. High Sensitivity: Door alarm contact sensor can be detected immediately any movement of a door or window. You can use our super strong alarm system to stop intruders. 2. Real Time Monitoring: When door or window is opened or closed, the sensor will push instant notification to your smartphone immediately. so you don't have to worry about your baby going out of house without notice, will easily know when your aged parents leave or arrive home and even can be clear when someone enters your home,shop,office ,etc. 3. Low Power Consumption: WiFi door sensor detector is made of ABS material, powered by 2xAA 3V lithium batteries (not included), 24 hours monitoring, 365 days of ultra long standby, energy saving and low power consumption, with a battery life of over 1 year. 4. Easy Installation: No need to use complicated tools when installation, just use the included double sided tape to experience worry free installation, with everything you need included in the box. 5. Wide Application: WiFi smart magnetic door sensor can prevent children from sneaking out and intruders from breaking in, and is widely used in families, villas, office buildings, conference rooms, hotels, etc. Specification: Item Type: Door Alarm Contact Sensor Material: ABS Working Voltage: 3V Working Current: 19 to 59mA Battery: 2 x 1.5V AAA battery (shipped without battery) Standby Current: ≤35uA Connection Method: WiFi (802.11b g n) Network Type: 2.4GHZ Standby Time: 10 to 12 months WiFi Distance: 30M (obstacle free) Installation Distance: ≤2cm (0.79in) Trigger Distance: Approx.2 to 3cm / 0.79 to 1.18in Working Temperature: -10℃ to 55℃. Package List: 1 x Door Alarm Contact Sensor1 x Door Alarm Contact Sensor Button2 x Double Sided Tapes1 x Instruction Manual Note: To ensure the effect, the distance between the emitter and the magnetic strip should be less than 10mm, and keep away from strong magnetic fields when installing