20/PCS PH Test Strips PH Meter PH Controller 1-14 Indicator Litmus Tester Paper
The smaller the number, the stronger the acidity, the larger the value, the stronger the alkalinity. PH 1-14 universal indicator papers for alkaline / tests. 1 Box PH Test Paper. Chart Intervals: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14.