Single roll dispensers come complete with 15' (4.6 m) roll of paper and color chart. Wide range papers show a distinct color change for each full pH unit change from pH 1 to 12. Hydrion Insta-Chek Single Roll pH Paper provides: 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 easily matched color separations / Accurate, reproducible readings with an immediate response