The Baker B6015 Sling Psychrometer is designed for portability and has a slide rule construction that quickly converts temperature to relative humidity. Its built-in reservoir holds sufficient water for several hours of testing and the thin bulb design gives fast thermal response. It features a non-mecury red spirt filled thermometer and the thermometer is constructed of shock-resistant glass; stems have deep-etched numerals and 1" scale division for easy reading. This psychrometer is ideal for measurement of comfort conditions in air conditioned environments, hospital operating rooms, storage areas and laboratories. Measures in°C Reading Only.