4 Pcs Tds Meter Water Quality Tester Filter Pen Testing Water Quality For Drinking Water /swimming 1.Highly efficient and accurate due to advanced microprocessor technology,The TDS meter one measurement can be completed within 5 seconds.2.TDS meter Built-in Digital Thermometer, meter, Display: and Easy-to-read LCD Screen.3.Long battery life : The TDS Meter used with 2pcs 1.5V batteries, can use more than 3 years, it will be power-off automatically after stop using in 5 minutes to save the battery.4.Application: Widely used in swimming pools, drinking fountains, aquariums, hydroponics, TDS testing, water quality testing, tester, solubility testing and more.5.High accuracy: +/- 2% Readout Accuracy Testing, the titanium alloy probe has high test accuracy, which can avoid the interference of magnetic field in water.Colour:Photo ColorMaterial:plasticSize:155mm X 31mm Package Contents:4 x water testing penOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.