6pcs TDS-3 Handheld Digital LCD Water Quality Tester Pen Temp/PPM Filter Water Purity Meter Low-voltage Protection

Low-voltage Protection

Simple and stylish minimal bluetooth earpiece is easy to control between voice calls and music

Heart Rate Sensor Smartphone OS Compatibility: Android 4

flexibly fitting smartphones with different widths

6pcs TDS-3 Handheld Digital LCD Water Quality Tester Pen Temp/PPM Filter Water Purity Meter Low-voltage ProtectionProduct Features: What is TDS: Total dissolved solids are the total weight of all solids(minerals, salts, metals, etc) that is dissolved in a given volume of water, express in milligrams per liter(mg L), or in parts per million(ppm). Use the TDS meter to: Check the performance of your water filter. Check the hardness. Make sure you always drink pure water. Hold function: Saves measurements for convenient reading Auto off function: Turn off meter after