Specifications: Hold function: saves measurements for convenient reading and recording. Auto-off function: turns off meter after 10 minutes of non-use to conserve batteries. This item can be used in water purifiers and filters food (vegetable fruits) & drink quality monitoring pools and spas aquariums hydroponics. Item Name: TDS Tester Material: Plastic Power Supply: 2 x LR44 Battery (Included) Features: Water Tester Water Purity Meter Portable Easy to Use Size: 13.7cm x 2.5cm x 1.4cm/5.39 x 0.98 x 0.55 (Approx.) Notes: Due to the light and screen setting difference the item s color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x TDS Tester