Advanced processor: automatically calibrated temperature; TDS tester measuring range from 0 - 9990ppm with 1ppm accuracy(Please receive the coupon code on the product page at checkout to get a better price.) Hold button: Holds measurement value when meter is removed from water for convenient reading and recording Temperature Button: Tests water in Celsius and Fahrenheit; 31 - 200F degree range, 1F accuracy Auto-off function: automatically shuts off after 10 minutes of inactivity to preserve battery life Convenient : Comes with a leather carry case and clip, ideal for on the go Instructions: Step 1: Remove the protective cap. <p >Step 2: Turn on the TDS meter. Step 3: Immerse the device in water or solution to the maximum immersion level. The height of the solution should not exceed 4cm (from the point of the pen). Step 4: The TDS value will be fixed on the display between 10-30 seconds. Hold down the “hold” key to lock the value. Step 5: Wipe off any remaining water from the pen with a cloth after finishing and replace the pen cap. Color: beige. Precision: +/-2%. Amplitude: 0-9990ppm. Item Dimensions: 155mm x 28mm x 15mm. Contents:1 x TDS Meter Tester.1 x Leather Case.1 x User Manual. Note: Data is manual measurements, please allow 1-40cm error, due to differences between light and screen, there will be a certain color difference, the specific received in kind prevail.