Welcome to our store! 100% new with high quality and great value. Ideal for checking TDS/salt (NaCl) levels in freshwater aquariums, ponds, and water purification systems. 3-in-1 Smart Pen combines TDS, EC, and a temperature meter for enhanced accuracy. Features automatic temperature compensation and a measurement range of 0-9999 ppm with +/- 2% accuracy. 4 Display Modes: Press the SHIFT button to switch between TDS - ppm & Celsius, EC - s/cm & Celsius, TDS - ppm & Fahrenheit, and EC - s/cm & Fahrenheit. Lock Function: Easily read and record measurements by pressing the HOLD button and then removing the device from the test solution. Auto-off Function: The instrument automatically shuts off after 5 minutes of inactivity. Conductivity: 0 - 9999 s/cm TDS: 0 - 9999 ppm Celsius: 0.1 - 80.0 Celsius Fahrenheit: 32.0 - 176.0 Fahrenheit Resolution: TDS: 1 ppm; EC: 1 s/cm Battery: 1x3.0V (CR2032) Accuracy: 2% Color: White Material: Plastic Size: 152 x 30 x 14mm Package Contents: 1 x TDS & EC Meter Only the above package contents are included; other products are not. Note: Light and different displays may cause the color of the item in the picture to differ slightly from the real item. The allowed measurement error is +/- 1-3 cm. Your satisfaction is our top priority. We are committed to providing the best service. If you encounter any issues after receiving the product, such as damage or incorrect quantity, please contact us immediately for the best solution!