For accurate pH measurements, these sticks have four distinct indicator dyes that are colour-fixed and non-bleeding to prevent the contamination of the sample. The larger scale and well-separated dyes on a durable plastic strip are easy to read, and the variety of ranges available cover many applications. Resolution: 1.0 pH (complete range), 0.3 to 0.5 pH (intermediate range), and 0.2 to 0.4 pH (narrow range). Each strip is 6 x 85 mm.