Very Easy to operate, quick testing, obvious results. Simplest and cheapest way to test water quality. Check the condition of your drinking water The electronic color tester is an effective tool that visually demonstrates differences between high TDS and low TDS water Features: Easy to operate and provides fast, clear results Provides a simple method to test water quality Used to assess water purity levels, allowing users to observe the condition of drinking water High precision Testing methods: Prepare two transparent cups of water (100 to 150 ml), one with tap water and the other with RO water Insert metal rods into both cups, turn the device on and begin the test. After 30 to 60 seconds, turn it off and remove the electrolyzer Caution: Avoid electric shock during use; do not touch the rods once the device is plugged in Testing Analysis Results: Black: Heavy metals Yellow: Dissolved acids, fluoride and organic matter Green: Arsenic, mercury, lead, copper, sodium Blue: Bacteria, viruses, carcinogens, chemical fertilizers, pesticides, etc. Red: Iron, rust and bacteria White: Lead, zinc, mercury, inorganic impurities Specifications: Plug: EU Plug Voltage: 220V Power cord length: 85 cm Iron bars length: 7 cm Size: 10.2 x 3.7 cm Quantity: 1 piece Note: 1. Transition: 1 cm = 10 mm = 0.39 inch 2. Please allow 0–3 cm error due to manual measurement. Ensure you are comfortable with this before purchasing 3. Due to differences in monitor displays, the image may not reflect the actual item color No retail packaging included Package Contents: 1 x Water Quality Testing Device