Digital TDS Water Tester with Backlit LCD & Hold

Compare dissolved-solids readings when checking a filter sample or recording changes in water. This pen-style TDS tester displays an estimated ppm value with a backlit LCD and hold function. It is for home and hobby users tracking TDS, rather than testing whether water is safe to drink.

• ✅ Compare samples in a simple routine — The digital ppm readout gives a value to record for each sample.
• ✅ Write down a reading after the test — The hold function keeps the displayed value available.
• ✅ Read the display in a dim corner — A backlit LCD illuminates the digits.
• ✅ Notice a changed screen indication — The stated colour change occurs above the preset threshold.
• ✅ Carry a tester to the sample — The pen-style body is easy to pack with your measuring kit.

Track TDS changes without mistaking them for purity

TDS means total dissolved solids. A pen-style TDS instrument estimates a dissolved-solids value from the water's electrical conductivity. Comparing readings under similar conditions can be useful when keeping notes on filter samples or changes in a hobby setup.

The stated measuring range is 0–9,990 ppm. The screen is described as changing to red above 50 ppm, but that threshold is a display setting, not a universal pass/fail limit or proof of contamination. TDS alone cannot identify particular substances, pathogens or establish drinking-water safety.

Select the purple or white body option; the purchase is one tester, not both colours. Two LR44 batteries are required and not included. Keep the electronics out of the sample and follow the operating instructions for immersion and cleaning.

The pen-style probe provides a TDS reading; it does not establish drinking-water safety.

The preset screen-colour threshold is not a universal water-quality pass/fail limit.

Technical details

• Measurement: estimated total dissolved solids (TDS)
• Stated range: 0–9,990 ppm
• Display: backlit LCD
• Function: data hold
• Colour indication stated: red above 50 ppm
• Power: 2 × LR44 batteries, not included
• Body options: purple or white
• Package: 1 selected TDS tester
• Limitation: does not establish drinking-water safety or identify individual contaminants

Choose your tester colour and add consistent TDS readings to your water-checking notes.

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