1. Simply press the testing strip to the object or liquid you are testing. in few seconds, take out the paper and using the color chart included, compare the color change of the paper to find out the acidity level of your testing subject.
2.Can not indicate the Acid or alkali solution when its density is lower than 0.01%.
3. Keep dry for the rest paper.
Paper Size: approx 45mm x 7mm (L x W)