No 9.18 what is written there is necessary for the calibration. I thought it might still not work that accurately, but it won't even work for the first step! It just shows 0 no matter what! I want this to work at least once. Useless! The money is gone!
TDS water quality tester - TDS water hardness meter (portable digital salt meter for water analysis)
9 Review
Accurate And Versatile Digital PH Meters For Food, Brewing, Hydroponics, Pools And More!
7 Review
Portable digital multimeter with sound continuity and thermocouple (electric tester) LTX DT-838
7 Review
Efficiently Test Your Antifreeze And Battery Acid With A 3-In-1 Refractometer
18 Review