These laboratory grade yellow-back thermometers are totally enclosed in Teflon. This effectively seals the liquid column from the test medium. Thermometer life is extended, and ‘like-new’ appearance of graduations and markings is retained by tough Teflon coating. Should breakage of thermometer happen during testing, test liquids are totally protected by coating. These thermometers may be safely used in caustic solutions and acids without affecting graduation readability, unlike traditional glass thermometers. Without suspension ring. Length: 305 mm.