Micro Essential Hydrion S/R Insta-Chek pH Paper 0.0-13.0Micro Essential Hydrion S R Insta Chek pH Paper 0. 0 13. 0 Hydrion Insta Chek pH Paper, the ultimate in wide range, general purpose pH papers has a distinct color match at each full pH unit:[0. 0][1. 0][2. 0][3. 0][4. 0][5. 0][6. 0][7. 0][8. 0][9. 0][10. 0][11. 0][12. 0][13. 0]. Hydrion Insta Chek pH Papers provide: A direct reading pH paper with the widest range available in a single paper A simple, single color match for all pH values Distinct and