Check the listing for details. SparkFun Temperature Sensor - Waterproof (DS18B20) B-1. Condition: New. Listed at 14.95 USD. New, bulk packaged. There are no marking or numbers on the product. I did a picture search on-line to get the description and information. Sold without any guarantee of use. This SparkFun Temperature Sensor (DS18B20) is a must-have for anyone interested in educational electronics. It is waterproof and perfect for use in science and nature projects. With its easy-to-read temperature display, this sensor is ideal for students and hobbyists alike. The sensor is compatible with a wide range of devices and is perfect for use in toys and hobbies. It is also ideal for use in educational projects, where it can be easily connected to a computer or other device for display and analysis. If you're looking for a reliable and versatile temperature sensor, this SparkFun Temperature Sensor is the perfect choice.