[4-in-1 Mode Alarm]: 1. General alarm. When the door is closed, it will stop; 2. Continuous alarm. Even if you close the door, it will continue to alarm; 3. Delay alarm. The time interval can be set freely, such as 2/5/10/20s, the alarm volume gradually increases from 0dB-108dB; 4. Doorbell mode. There is a "ding " sound when the door is opened. [Door Alarm]: Can be used for doors, , refrigerators, filing cabinets, swimming pool sliding doors, etc. 108dB siren sound can effectively deter intruders/thieves. At the same time, it can notify you of what is going on. [Battery Powered]: This door alarm requires 2 AAA alkaline batteries(No Battery). When the battery is low, the LED light on the siren will flash every second as a reminder. [Easy Installation]: Just tear off the sticker and directly on the location you want to install. First determine where you want to paste. The distance between the alarm and the magnetic strip must be less than 10mm during installation. material: plastic Color as shown Package Contents: 2 x Security Door Alarm Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.