pH pens – for the quick and precise determination of pH, acidity levels and the content of wood components in paper, documents, photographs and graphics.
- NK-001 - Paper alkalinity test
- NK-002 - determination of wood components in paper
- NK-003 - pH scale from 1 to 12
- NK-004 - pH scale from 3.8 to 6.0
- NK-005 - pH scale from 5.8 to 8.2
- NK-006 - pH scale - 3.8 to 6.0 and 5.8 to 8.2