EC Measuring range: 0 to10000uS/cm 10.01-19.99ms 20.1-400mS/CM Resolution: 1 uS/cm; 0.1 mS/CM; Accuracy: ±2% of reading TDS Measuring range: 0 to 1000ppm 1000ppm to 10000ppm 10.1 to 200.0ppt Resolution: 1ppm; 0.1ppt Salinity Measuring range: 0.00 to 25.00% Resolution: 0.01% Accuracy:0.01-5.00% (±0.1%) 5.10-25.00% (±1%) PH Measuring range: 0.01-14.00pH Resolution: 0.01pH Accuracy:±0.05pH temperaturerange: 0.1-60.0℃ 32.0-140℉ Conductivity EC: Supports 3-point calibration automatic identification (1413us 12.88ms and 111.8ms) with 3 calibration points (1413uS/cm 12.88mS/CM 111.8mS/CM) pH: 1 point (6.86) or 2 points (6.86 4.00) (6.86 9.18) or 3 points (6.86 4.00 9.18) can automatically identify the calibration solution Size and weight:183 x 37 x 37mm(7.2 x 1.5 x 1.5in)/90g(3.2oz) Color: As Shown Material: plastic Package Contents: 1 x 5 In 1 Digital PH TDS EC Meter Pen 1 x English instruction manual Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.