Technical parameters: -- Voltage: DC 9V (9V alkaline batteries) -- Alarm sound: 120 dB -- Start-up delay: 15 seconds -- Installation ways: Back-magnetic or adhesive paste -- Product Dimensions: 100* 53 * 28mm -- Package Size: 105 *60 *42mm The product has passed the test by China Public Security Testing Center(Certificate No. 990353). It aims to protect your property by giving out alarm sound when it senses vibration, shaking, striking and moving. Please kindly read the following instruction carefully: 1. Install one piece of 9V battery in the alarm(please check the polarity of the battery) 2. Attach the alarm to door or window. (there is magnetic bar inside the alarm) 3. Switch on the alarm and it will be on ALERT for 15 seconds. If there is any vibration, the alarm will sound for 25 seconds. (the beep sound is over 110dB) 4. If the vibration contiues, the alarm wil sound again. 5. When the sound is low, please replace the battery. If you don't use the alarm for a long time, please remove the battery. Note: If you are buying a remote control vibration alarm, then besides the above functions, there are still the following two functions: 1. Settings: Click the button deployment, three seconds later into the security alert. 2. Disarm