Product name: 7 in 1 water quality test pen Measuring range: PH/ORP/EC/TEMP/SALT/S.G/TDS Product size: 185*37*24mm Battery: 3*1.5V button battery Product measurement range: 1. PH value 0-14 2, TDS value 0-200000ppm 3. EC value 0-200000㎲/cm 4. Salinity 0-20% 5. ORP negative potential ±1999MV 6. H2 hydrogen rich 0-2400PPb 7. The specific gravity of S.G seawater is 1.000-1.222 8. Temperature 0-60℃