Very Easy to operate, quick testing, obvious results. Simplest and cheapest way to test water quality. Test your own drinking water and observe its condition. The electronic color tester is a tool that visually demonstrates differences in water samples. Features: Easy to operate with quick and clear results Provides a simple method for testing water quality Helps assess water purity levels High precision Testing Methods: Prepare two transparent cups of water (100 to 150 ml), one with tap water and one with RO water. Insert the metal rods into both cups, turn the device on, and begin the test. After 30 to 60 seconds, turn it off and remove the electrodes. Caution: Avoid electric shock. Do not touch the rods when 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 product color. Thank you. No retail packaging included Package Contents: 1 x Water Quality Testing Device