EC Measuring range: 0 to10000uS or cm 10.01-19.99ms 20.1-400mS or CM Resolution: 1 uS or cm 0.1 mS or CM Accuracy: 2 percent 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 percent Resolution: 0.01 percent Accuracy:0.01-5.00 percent ( 0.1 percent ) 5.10-25.00 percent ( 1 percent ) 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 or cm 12.88mS or CM 111.8mS or 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) or 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.