Bentop TDS-3 Water Quality Test Meter 3 Button Digital Meter Features Automatic Temperature Calibration, Carrying Case, 0 - 9990 ppm Measurement Range Light Grey 1. ADVANCED CPU-Automatically calibrated per temperature, 0 - 9990 ppm TDS Measurement Range with 1 ppm Resolution 2. MEMORY FUNTION- Holds measurement value when moving out of water for convenient reading and recording 3. TEMPERATURE FUNCTION- Test water temperature, 31 - 200 F degrees, 1 F degree resolution 4.AUTO OFF - shuts off automatically after 10 minutes of non-use to conserve batteries 5.WITH CARRYING CASE - Comes with leather carrying case, ideally to carry around and test water quality at various places