4 in 1 Mode: This alarm features 4 modes. 1. Timing alarm (emits a 'Di-Di-Di' sound increasing from 0dB to 108dB if the door remains open for 3/15/30/60 seconds) 2. General alarm (alarm stops when the door is closed); 3. Constant alarm (continues sounding even after the door is closed); 4. Door opening chime (produces a single 'Ding-Dong' sound when the door is opened). Loud 108dB Alarm: The door and window alarm helps effectively deter intruders or thieves with a loud 108 dB alert. You can easily select the appropriate mode based on your needs. Easy to Install: Simple peel-and-stick setup allows quick installation on most freezers, refrigerators, or doors without tools. Package includes 2 fridge alarms, 2 magnetic strips, double-sided adhesive tape, and user manual. Electronic instructions are shown in the eighth image. Installation Note: Ensure the alarm and magnetic strip are properly closed. The distance between them should not exceed 0.78 inches. Both parts must be aligned using the alignment arrows. Uses 2 AA batteries (not included), which can last up to 2 years. Widely Used: Magnetic trigger door alarm sensor provides security for home entry points including doors and windows. Suitable for use on safes, cabinets, freezers, refrigerators, sliding pool doors, shops, offices, apartments, hotels, and more.