This soothing method is a great alternative to rectal thermometers. The one-piece constructed orthodontic nipple measures most temperatures within approximately 90 seconds. Features include clinical accuracy, memory recall of last reading, waterproof design for easy cleaning, lullaby fever alarm indicating temperatures above 99.5oF and continuous monitoring with automatic shut-off after approximately 25 minutes. Is phthalate free and conforms to the safety requirements of the US Consumer Products Safety Commission for pacifiers. Self-contained, non-replaceable battery is sealed for added safety..