Specifications: 108 dB Loud Alarm 4 Feature Modes - - Time Delay, General Alarm, Constant Alarm, Doorbell, easy set the appropriate mode according to your need. Wireless Alarm Battery Operated, it need two AAA alkaline batteries ( not included ). Low Consumption Design, they can work for over 2 years. Low Battery Warning, when it need replace batteries, the LED light will flash once every second. Self-Adhesive, easy to install and operate. Product Size: 3.4 x 1.7 x 0.4 inch Multi-Using: 1. Fridge, Refrigerator, Freezer door alarm Reminder. 2. Window door alarm for home safety 3. Cabinet door alarm in store security. Package Including: 1 x refrigerator alarms 1 x magnetic stripe 1 x user manual Wireless freezer alarm: It will only alert you when freezer door has been left open for 3s or 15s or 30s or 60s, it will not annoying you while you want the door open, you can easily to set the delay time as your need 108dB Loud Alarm: Door and window alarm helps detecting intruder or thieves effectively by 108dB alarm, also door open chime will remind you if children or pet or others are coming or leaving. 4-in-1 Mode: This alarm with 4 modes. 1. Time Delay Alarm (sounds Di-Di-Di from 0dB to 108dB if door stays open for 3 or 15 or 30 or 60s) 2. General Alarm (alarm stop if door closed) 3. Constant Alarm (constant alarm even door closed) 4. Door Open Chime (sounds DingDong once door opens) Easy to Install: Simple peel and stick on most of freezers or fridges or any door without any tools. Widely Use: Magnetically triggered door alarm sensor protecting house by door window entry and suitable for safe box, cabinet, Freezers, Refrigerators, pool sliding door, store, office, apartment, Hotel etc.