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/15s/30s/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/thieves effectively by 108dB alarm,also door open chime will remind you if children/pet or others are coming/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 3/15/30/60s) 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/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.