The Extech EC100 is a waterproof (meets IP65 standard) Conductivity/Temperature Meter with a high-accuracy multi-ranging sensor. Features an auto power off with disable. Units of measure include µS/cm, mS/cm, ppm, and ppt. Featuring adjustable automatic temperature compensation, the EC100 includes a protective sensor cap and four LR44 button batteries. Conductivity standards sold separately (required for calibration).