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