Range: 0-199.9ppt Resolution: 0.1ppt Accuracy: 2 percent F.S Temperature Compensation: 0Celsius-50Celsius Operating Temperature: 0Celsius-50Celsius Battery: 4x1.5V(without batteries) Operating steps: 1. Remove the protective cap. 2. Wash electrodes in distilled water, and dry it by filter paper. 3.Turn on by "ON-OFF" switch. 4. Put electrode into liquid which is to be test, and stir lightly. Wait until the digital is stable, read the final value. 5. After use, wash electrodes, put on protective cap. Calibration: 1.Immerse the meter in the distilled water.Activate it about some hours. 2.Immerse the meter in 35ppt calibration solution (at 25Celsius),and stir it gently. 3.Allow the reading to stabilize and turn the calibration trimmer with a small screwdriver until the display shows 35ppt. Colour:black Material:plastic Size:170x50x28 mm Weight:51g Package Contents: 1 x Salinity Meter Only the above package content, other products are not included. Note: Light 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.