The Fisher Scientific 0666423 is a Refrigerator/Freezer Thermometer. This thermometer is designed to accurately measure the temperature within your refrigerator or freezer to ensure that it is at the optimal level for storing food or other items. This product is sold individually. It is a critical tool for maintaining the safety and quality of perishable goods, including food, pharmaceuticals, and other temperature-sensitive items. It’s designed for ease of use and provides accurate, reliable readings.