• Code:

  4595

• Testing pen

• Net weight: grams 19 -  Gross weight: grams 21,3

Testing pen
Acid-testing pen.
Used to check the acidity or alkalinity of documents.
Once a line has been traced on the material, it turns purple if it is alkaline (pH greater than 6.8). If, instead, the tested document is acidic (pH less than 6.8) the line will turn yellow.
Please note that test results on coloured documents are not always accurate.

Testing pen