Feature: 1. PORTABLE AND EFFICIENT: Our water quality testing pen is a portable instrument that allows for quick measurement and evaluation of various indicators and parameters of water bodies. 2. COMPREHENSIVE COMPOSITION: Typically consisting of a pen shaped device and a measurement electrode, the measurement electrode can be immersed in the water sample being tested. It generates corresponding electrical signals through chemical responses or physical changes with substances in the water sample. The instrument converts these electrical signals into readable numerical values, displaying the measurement results of water quality indicators on a screen or indicator lights. 3. EASY TO USE: Our water quality testing pen is extremely convenient. With its compact size, it is easy to carry and suitable for outdoor and field use, as well as laboratory and industrial environments. Users simply need to insert the electrode into the water sample, press the operation button, and quickly obtain the measurement results of water quality indicators. 4. WIDE APPLICATIONS: The water quality testing pen is widely used in fields such as drinking water testing, environmental monitoring, water pollution prevention and control, and water treatment. By monitoring water quality indicators, it can assess the degree of water pollution and determine if the water quality meets relevant standards and requirements, providing convenient and accurate data for the protection and improvement of water environment. 5. RELIABLE AND ACCURATE: Our water quality testing pen is designed to provide reliable and accurate results. It ensures accurate measurements, allowing users to make informed decisions and take necessary actions to maintain and improve water quality. Specification: Item Type: Water Quality Tester Size: Approx. 157 x 37 x 14mm / 6.18 x 1.46 x 0.55in Battery: AAA x 2 (not included) Detection Functions: Chemical Oxygen Demand (COD), Total Organic Carbon (TOC), Total Dissolved Solids (TDS), Ultraviolet Absorption Value (UV275), Electrical Conductivity (EC), Temperature (T) Calibration: Long press the button in measurement mode to enter the calibration interface. The screen will prompt "Insert the instrument into distilled water, press the measurement button to calibrate!". Insert the instrument probe into distilled water and press the button to start calibration. After calibration is completed, it will prompt "Calibration success!" and return to the measurement page. Measurement: Insert the instrument probe into the sample water, press the button to measure. After measurement, the default 3 parameter mode of the instrument will display COD, TOC, and TDS. Setting it to 6 parameter mode will display COD, TOC, UV254, TDS, EC, and temperature. The instrument will also score the water quality based on the test data and display different backlit colors on the screen according to the water quality judgement, Poor red, Fair yellow, Good green, Excellent blue. Settings: Long press the button for 3 seconds when the instrument is off to enter the main menu. There are 4 sub options: Language, Display, Calibration, Exit. Use the button to choose the option and press the button to confirm the selection. Weight: Approx. 114.00g / 4.02oz. Package List: 1 x Water Quality Test Pen 1 x User Manual