Check the listing for details. TDS/Temp Meter. Condition: New. Listed at 7.00 USD. This Total Dissolved Solids (TDS) meter can be used to: Check the performance of your water filter or water purifierTest for water hardness (1 grain = 17ppm)Monitor the quality of your drinking waterMonitor pools, spas, aquariums and hydroponics Features:Hold function: Saves measurements for convenient reading and recording Auto-off function: Turns off meter after 10 minutes of non-use to conserve batteries Dual Range: Measures from 0-999 ppm with a resolution of 1 ppm and from 1,000 to 9,990 ppm with a resolution of 10 ppm. Over 999 ppm, the display is a 3-digit numerical value x10. For example, a ppm of 1295 is displayed at 129 x10. Note that the "x10" in the display is very smallAccuracy +/- 2% of Full Scale Measures temperature in Centigrade and FahrenheitBattery: 2x LR44 1.5V Button Cells (Included) Item size:155mm x 30mm x 21mm (6.1" x 1.2" x 0.8") Weight: Approx 76g (2.7oz) Package Includes:1X TDS Water Quality Test Meter2X LR44 Batteries