Fullerton, Calif.-based Good Water Warehouse introduces OAKTON Instruments’ new Waterproof Pocket Sized TDSTestrs and ECTestr as the most accurate available in this category. Automatic shut-off conserves battery power. Hold function freezes readings for easier viewing. Automatic temperature compensation ensures accuracy. These are the only pocket sized TDS and conductivity instruments in the world that float, are waterproof and dust proof, and have replaceable sensor assemblies.