Ideal for commercial use. Includes a carrying case with belt clip. Highly efficient and accurate due to its advanced microprocessor technology. Hold Function: saves measurements for convenient reading and recording. Auto-off function: the meter shuts off automatically after 10 minutes of non-use to conserve batteries. Measurement Range: 0-9990 ppm. From 0-999 ppm, the resolution is in increments of 1ppm. From 1000 to 9990 ppm, the resolution is in increments of 10ppm, indicated by a blinking `x10` image. Built-in digital thermometer. Display: large and easy-to-read LCD screen, Factory Calibrated: our meters are calibrated with a 342 ppm NaCI solution, Meters can be recalibrated with a mini-screwdriver. Also available in “x10” mode: reads in increments only o F10 ppm (0-9990 ppm).