CDN TA20 Audio Visual Refrigerator Freezer Alarm - Set of 2 Battery and instructions included 39-inch sensor cable with suction cups; Velcro tabs firmly attach case to outside surface Made of shatterproof ABS plastic; dual progress display Audio alarm sound when refrigerator reaches 46 degrees F or freezer reaches 15 degrees F Maintain food-safe temperatures in your refrigerator and freezer with innovative thermometer