EnviroKleen™ certified thermometers feature black, non-toxic, biodegradable, Enviro-Safe® liquid.Black liquid against lead-free, yellow back glass for easy readability and fewer reading errorsIdeal for use in chemical/petrochemical laboratories, universities, scientific institutions, food and beverage processing, pharmaceutical and medical industries, dairies, breweries and distilleriesManufactured and tested by our USA quality teamTraceable to NISTIncludes multi-language (English, French, German, Italian, Portuguese, and Spanish) Statement of Accuracy and Traceability, non-roll fitting and individual serial numberShould you require an individual Thermometer Calibration Report, factory calibrated thermometers or custom calibration services are available.