Review on 📝 Lineco Paper pH Testing Pen: Optimized for Paper and Paperboard Products. by Kim Sanchez

This pen is not working. I tested it on very old paper from 150-200 years ago. Tested on old but not real old paper. I tested this on a fabric known as interlacing. Checked on new paper. New paper and serviettes are produced acid-free. It did not appear acid-free or low-acid on either the tissue or the stationary material. It turned out sour, and it showed sour on old paper and really old paper. The only thing it was low acid for was paper that I had treated with bleach.