The mechanical pH pencil Hydrion measures the pH of any surface to the nearest maximum pH value. The Hydrion pH pen can be used to test irregular or uneven surfaces, and is also effective on porous materials and impermeable solids. It offers clear, bright, unique color matches at every interval of 1.0 starting at pH 0.0-13.0.

The color chart has pH matches to [0.0] [1.0] [2.0] [3.0] [4.0] [5.0] [6.0] [7.0] [8.0] [9.0] [10.0] [11.0] [12.0] [12.0] [13.0]

The pH pencil is used to detect acid or alkali residues and can be used to measure the pH of any of the following:

Paper, lumber, concrete , cement, plasterboard, prepainted surfaces, painted surfaces, textiles, skins, ceramics

Packaged 3 pH pencils per box.