Accurate and reliable 3 in 1 measurement Professional TDS, EC and Temperature pen 3 in 1. Upgraded with microprocessors and precise algorithms to improve test accuracy. Data lock with HOLD button lets you save the current test reading for later reference. Titanium alloy probe delivers precision measurements and durable performance. Automatic Temperature Compensation (ATC) provides reliable results regardless of water temperature or magnetic interference. Designed to test the purity of drinking water to help ensure health and safety. Wide applications Suitable for water quality testing in drinking water kits, home drinking water systems, and purification setups such as RO or DI systems. Useful for monitoring beverages, aquariums, hydroponics (nutrient solutions), swimming pools, SPAs, and for commercial or industrial water quality checks. Helps verify that a reverse osmosis system is functioning properly and signals when filters may need replacement. Quick test and power efficiency Measurement range: 0–9990 ppm. Turn the device on, stir water gently, and stable readings appear on the LCD within seconds. Powered by two LR44 button batteries, with typical use lasting more than 2–3 years. Auto poweroff after 5 minutes of inactivity to conserve battery life. Why monitor TDS TDS levels can alter water taste, making it salty, bitter, or metallic, and may indicate the presence of minerals that could affect health. Excessively TDS can cause hard water, pipe fouling, dryness of hair, and spots on dishes. The EPA recommends a maximum TDS level of 500 ppm for drinking water; using a TDS meter helps maintain safe and palatable water. Use scenarios Home and office drinking water quality checks to confirm safety and taste acceptability. Regular verification of RO/DI filtration systems to ensure proper operation and determine when filter replacement is needed. Monitoring hydroponic nutrient solutions, aquarium water, or pool and spa water to maintain conditions. Notes Reads TDS (ppm) while also providing EC and temperature measurements. HOLD function saves the current reading for recordkeeping and comparison. ATC and the titanium alloy probe help ensure accurate results across varying water conditions.