1.Highly efficient and accurate due to its 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 cycle: 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 Color Material:plastic Size:155mm X 31mm Package Contents: 4 x water testing pen Only 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.