Hard to find high-end Hydrion brand pH paper. New, never opened. Approx. 90 uses each. Designed for mid-range pH buffer solutions but can be used for any solution. Useful for homeschooling science experiments, those who want to measure the progress of their acid-alkaline balance diet, etc. Low price (compare with $24.99 on Amazon.ca when it's available) plus save the shipping fee. Have two new, never opened, to sell and one that has been used for just one test. $15 each for the new ones, $13 for the opened one. Will make a deal if you buy two or three.