1ATC FUNCTION: Multi function multi parameter test pen OW100 can perform salinity, TDS, EC and temperature measurement, can display temperature reading on LCD at the same time. With automatic temperature compensation (ATC) 2LCD DISPLAY: Large screen easy to read data display, two line subtitle LCD with backlight. Ingenious design structure is scientific and reasonable 34 IN 1 MULTI FUNCTION: Fast, efficient, accurate, portable test pen that integrates salinity, TDS, EC and temperature measurement to fully meet your measurement needs 4WIDE APPLICATION: Widely used in aquariums, aquaculture, laboratories, chemical reactions, food brewing, water purification, swimming pools, institutions, etc. 5ENVIRONMENTALLY FRIENDLY ABS: Water quality meter is made of good quality ABS material, possess impact resistance, scratch resistance, environmentally friendly Item Type: Water Quality Meter Model: S-100 Battery: 3 x LR44(not included) Material: ABS Uses: Widely used in aquariums, aquaculture, laboratories, chemical reactions, food brewing, water purification, swimming pools,institutions, etc. Basic Parameters: Measuring Range: Salinity: 0.00-25.00%/10.1-200ppt; TDS: 0-10000ppm/10.1-200ppt; EC: 1-10000s/cm; 10.01-19.99ms; 20.1-400ms/cm; Temperature: 0.1~60 1 x Water Quality Meter 1 x User Manual