Features: brand new and high quality Automatic temperature compensation accounts for changes in temperature automatically .What's more! PH meter No need any adjustment screwdrivers, just finish the calibration with auto calibration button. High accuracy: Ensure your pool, normal hydroponics ph. or even drinking water has a perfect pH balance and safe for use with digital pH meter precision pH accuracy. This digital pH meter is suitable for testing PH value of drinking water, pool, aquariums, spas, hydroponics, food, wine, brewing, milk, Cosmetics, chemical, metallurgical, environmental for protection, pharmaceutical, biochemical and other solutions for pH value monitoring. Large LCD display makes the reading more clear and easier, stable the value in 4-5 seconds. This pH water meter is economical and suitable for various industries which need pH testing. Measure range: 0.00-14.00pH, Resolution: 0.01pH, Accuracy:0.01pH. Specifications: Material: ABS Size: Approx 155x29mmx16/6.1x1.1x0.6 inch Color:Blue/Red/Yellow Warm tips STEP 1: Turn open pH meter, Clean the electrode in distill water STEP 2: Immerse the electrode in pH 6.86 standard buffer solution STEP 3: Press the "CAL" button. Wait until the display digital is 6.86pH and steady STEP 4: Clean the electrode in distill water and dry it, immerse the electrode in Ph 4.00 standard buffer solution STEP 5: Press the "CAL" button. Wait until the display digital is 4.00pH. Then complete pH 4.00 calibration STEP 6: Clean electrode and dry it, put the meter into PH 9.18 standard buffer solution. Check if reading is correct between 9.17-9.19pH Note: Please allow 1-3cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package includes: 1 x PH Meter 3 x Calibration Solution 1 x User's Manual