Features: - PH range 1.4-3.0, 20 strips per pack With distinct color PH scale for result comparisons. - Indicator papers used in science experiments and other fields to test the PH of a substance. - The indicator paper set comes complete with PH readings in the range of 1.4-3.0. For a better testing effect. Specifications: Type : PH Test Material: Paper Size: 6.5 x 4.5cm (L x W) Package included: 20pcs/box * Free Chlorine Test Paper Strips Notes: 1. Manual measuring, please allow 1 ~ 3mm error,thank you. 2. Due to the difference between different monitors, the picture may not reflect the actual color of the item. We guarantee the style is the same as shown in the picture.