Specifications: 108 dB loud alarm with 4 feature modes – Time Delay, General Alarm, Constant Alarm, and Doorbell, allowing you to select the appropriate mode based on your needs. Wireless alarm operates on two AAA alkaline batteries (not included). Low power consumption design enables operation for over 2 years. Low battery warning indicated by LED flashing once per second when battery replacement is needed. Equipped with self-adhesive backing for easy installation and operation. Product size: 3.4 x 1.7 x 0.4 inches. Multi-use application: 1. Refrigerator, freezer, or fridge door alarm reminder. 2. Window or door alarm for home security. 3. Cabinet door alarm for store security. Package includes: 1 x refrigerator alarm, 1 x magnetic strip, 1 x user manual. Wireless freezer alarm activates only when the freezer door has been left open for 3, 15, 30, or 60 seconds, preventing unnecessary alerts during normal use. Delay time can be easily adjusted as needed. 108 dB loud alarm helps detect unauthorized entry through doors or windows. The door opening chime provides an ble alert when doors are opened, useful for monitoring children or pets. 4-in-1 modes: 1. Time Delay Alarm – emits a "Di-Di-Di" sound increasing from 0 dB to 108 dB 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 Open Chime – produces a "Ding-Dong" sound each time the door opens. Easy to install – simply peel and stick on most freezers, refrigerators, or any door surface without tools. Wide application – magnetically triggered door alarm sensor suitable for use on doors and windows for home protection, as well as on safes, cabinets, freezers, refrigerators, sliding pool doors, stores, offices, apartments, and hotels.