4 in 1 Mode: This alarm with 4 modes. 1. Time-out alarm (sounds 'Di-Di-Di' from 0dB to 108dB if the door is left open for 3/15/30/60s); 2. General alarm (alarm stop if the door is closed); 3. Constant alarm (constant alarm even the door is closed); 4. Door opening chime (sounds "DingDong" once the door is opened) 108dB Loud Alarm: The door and window alarm helps to effectively deter intruders/thieves with 108dB loud alarm. You can easily set the appropriate mode according to your needs. Easy to Install: Simple peel and stick installation, easy to install on most freezers/refrigerators or any door without any tools. Installation Note: Make sure to close the alarm and the magnetic strip, the installation distance between them should not exceed 0.78 inch. The 2 parts should be aligned by their alignment arrow. (Batteries are not included) Widely Used: Magnetic triggered door alarm sensor protecting home through door window entry and suitable for safe, cabinet, freezers, refrigerators,