Comparator Paper pH 3.6 - 5.1
Comparator Paper PH 3.6 - 5.1, 10 Books of 20 Strips per pack
Johnson Test Papers Comparator Paper pH 3.6 - 5.1 Available at World Lab Supplies.
Remove one of the papers from one of the books within the pack and dip it into the solution for around one second. Compare the paper against the colour chart provided.
10 Books of 20 Strips per pack