High Quality Portable 6 in 1 S.G/PH/EC/SALT/TEMP/TDS Meter Digital Water Quality Tester High precision Tester - Bluetooth Type Specification: pH Measuring Range: 0.00 -14.00 pH Resolution：0.01 pH Accuracy: ±0.03 pH EC Measuring Range: 0-19900 us/cm; 0-199.0 ms/cm Resolution：1us/cm (<1999us/cm) 10us/cm(>1999us/cm) 0.1ms/cm Accuracy: ±2% F. S TDS Measuring Range: 0-19900 ppm; 0- 199.0 ppt Resolution: 1ppm (<1999ppm) 10ppm (>1999ppm) 0.1 ppt Accuracy: ± 2% FS SALINITY Measuring Range: 0-199.0 ppt; 0% -20% Resolution: 1ppm (<1999ppm) 10ppm (>1999ppm) 0.1 ppt, 0.01% Accuracy: ± 2% FS S.G Measuring Range: 0.990 – 1.400 Resolution: 0.001 Temperature Measuring Range: 0-50 °C (32-122°F) Resolution: 0-01 °C (0.2°F) Accuracy: ± 1. °C Temperature Compensation: 0°C-50 °C Operation Environment: 0°C-50 °C Battery: 4x1.5V Size/Weight：18x4.5x4.5cm / 110g The instruments will not switch automatically when connected to Bluetooth, but will switch off automatically after 8 minutes of no operation when disconnected from Bluetooth.