The iSpring TDS meter is a digital device designed to measure Total Dissolved Solids (TDS) in water, using the ppm (parts per million) scale to indicate the concentration of dissolved solids. Additionally, water temperature affects TDS readings. The iSpring 3-button TDS meter incorporates two sensors: one for TDS and another for temperature. Its CPU automatically calibrates TDS values based on water temperature for precise readings. With a measurement range of 0 - 9990 ppm at 1 ppm precision, this meter offers one of the highest ranges on the market for its size and cost. It also functions as a thermometer, with a temperature measurement range of 31 - 200°F at 1° precision. Compact in design and accompanied by a carrying case, the ISPRING TDS meter is a convenient and portable tool for assessing water quality anywhere, be it at home, in restaurants, at work, or while on the go.