Gravity: Analog TDS Sensor/Meter for Arduino _Maker so all you have to

so all you have to do is solder on straight or stacking headers and the terminal blocks

Sensirion SGP40 Datasheet

The onboard micro-SD card reader is accessible through the SD Library

The Arduino MKR WAN 1300 is able to run with or without the batteries connected and has limited power consumption

with a black powder-coated finish

Gravity: Analog TDS Sensor/Meter for Arduino _Maker so all you have toThis is an Arduino compatible TDS Meter Kit for measuring TDS value of the water, to reflect the cleanliness of the water. It can be applied to domestic water, hydroponic and other fields of water quality testing. TDS (Total Dissolved Solids) indicates that how many milligrams of soluble solids dissolved in one litre of water. In general, the higher the TDS value, the more soluble solids dissolved in water, and the less clean the water is. Therefore,