Feature:        1. LCD Display: The large, easy to read LCD screen includes simultaneous temperature readings for your convenience.     2. Automatic Temperature Compensation: Three different nonlinear EC to TDS conversion factors (KCl, 442TM, NaCl), automatic temperature compensation using three temperature coefficients.     3. Multi Function: Automatic shutdown function, data hold function and low battery indicator, multi function, simple operation.     4. IP67 Waterproof: Digital calibration (button) to any point within the meter range, IP67 rated waterproof housing, not afraid of damage to the inner core.     5. Four Scales: Portable water tester is made of sturdy ABS material, wear resistant and durable, and the four scales are µS, mS, ppm, ppt.           Specification:        Item Type: 4 in 1 Water Quality Test Pen Material: ABS Weight: Approx. 168g / 5.9oz EC Range: 0 to 9990 µS; 0 to 9.99 mS TDS Range: 0 to 8560 ppm (mg/L) PH range: 0.0-14.0 pH Temperature Range: 0.1 to 50°C; 32 to 122°F Resolution: PH :0.1 pH EC: 0-999: 1 µS; 1000-9990: 10 µS; 0-9.99mS: 0.01mS TDS: 0-999: 1ppm/1000-9990: 10ppm Temperature: 0.1 °C/°F Accuracy: PH :+/- 0.1% EC/TDS: +/- 2% Temperature: +/- 1% °C/F Probe: Detachable Electrode Housing: IP67 Waterproof Battery: AAAx2 (Not Included) Uses: Ideal for Testing Water, Swimming Pools, Aquariums, Spas, Hydroponics, Food, Wine and Beer Making, Etc.            Package List:    1 x Water Quality Test Pen    1 x Lanyard    1 x User Manual    3 x Detection Powder Pack