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[Water Quality Testing Must-Have]: The iSpring TDS meter is a great water quality test tool for drinking water, water filtration and purification systems such as RO systems or DI systems, aquariums, hydroponics (test nutrients), pools and spas, commercial and industrial applications and more. The TDS meter is great for checking your tap water quality and knowing when to change a filter.
[Accurate and Easy-to-Use] Highly efficient and accurate due to its advanced microprocessor technology. The TDS reading will be displayed on the LED screen in ppm (parts per million). TEMP button: Display temperatures. HOLD button: Lock and record readings. Auto-off Function: Shuts off automatically after a few minutes of inactivity.
[Durable and Convenient] Sturdy plastic housing, light weight(1. 76 oz), and included carrying case with belt clip for easy portability to any indoor or outdoor water testing site. A trustworthy multifunctional TDS pen to know TDS and temperatures of water in any home, workplace, lab, or industrial environment.
[Value Package] iSpring TDS meter x 1, Portable Leather Carrying Case with Belt Clip x 1, User Manual with TDS Chart x 1.
[Top-Notch Customer Service] Backed by a risk-free 30-day money-back and extended manufacturer upon registration at iSpring. Lifetime CS and tech support from Atlanta, GA. Please contact us if you have any questions or concerns. We're here to help!

A TDS meter (aka ppm pen, nutrient tester, TDS stick) is an inexpensive and convenient digital tool to instantly check your overall water quality. TDS stands for Total Dissolved Solids, which is any salt, metal or mineral in the water. With the push of a button, the TDS meter tells you your overall water purity level, which will be displayed on the screen in ppm (parts per million). The lower the TDS level, the purer the water, with 0 ppm being pure H2O.
The TDS meter is great for checking your tap water quality and knowing when to change a filter. The TDS meter is a great tool for drinking water, water filtration and purification, colloidal silver, hydroponics (test your nutrients), aquariums, RO/DI systems, pools and spas, commercial and industrial applications and more. The TDS meter is a rugged model that includes a protective carrying case. Pressing on the temperature button allows you to test the temperature of the water (allow 1-2 minutes for an accurate reading for the temperature compensation).
This is the world's most popular handheld TDS meter for both industry professionals and household use.