Double probe Black/White easy-to-clean case Greentest 3F is made to check the nitrate content in fruits, vegetables, meat, fish and the content of total dissolved solids (TDS value and water hardness) in water. Greentest 3F can not only quickly and accurately detect the safety of more than 60 most common foods, but also the quality of drinking water. The latest version is equipped with a capacitive screen, which is more sensitive to touch. Bluetooth module is added along with connection to the mobile APP for data storage and sharing. Timer function is added to help control the cooking time.