For the rapid determination of pH values from 0–14. The Ultrafast test set consists of two 15-foot rolls of pH paper—the Insta-Chek 0–13 and the Ultra-Sharp 12.5–14 test papers. The Insta-Chek 0–13 is a general-purpose, immediate response, wide range paper with a different bright color for each pH value from 0–13. The Ultra-Sharp 12.5–14 test paper is ideal for determining high pH values. It exhibits crystal clear color changes, from a bright blue at 12, through green at 13 and finally to sunny yellow at 14. Used in tandem, these two papers span the entire pH scale from 0–14. Refill package contains five 15-foot rolls of the Insta-Chek 0–13.