High Precision LCD Digital TDS Control Meter Handheld Water Purity Filter Tester Presenting a WIDE & EASY-TO-READ LCD DIGITAL SCREEN for hassle-free reading and viewing. Precise results & reliable efficiency every time. Thanks to its high-end microprocessor innovation. Featuring a HOLD button that allows you to save & hold data for stress-free reading & recording. Made of robust Plastic housing supported w/ ADVANCED ELECTRONIC mechanism for guaranteed longevity. Its professional & portable construction makes this the ideal tool for commercial & personal use.