| Description | These Low Contrast Flip charts contain 5 pages of various contrast levels showing 5 Lea Numbers® on each page. Optotype size is 9.5M. Contrast levels are 25%, 10%, 5%, 2.5% and 1.25%. These flip charts can be used at several different distances. | These Low Contrast Flip charts contain 5 pages of various contrast levels showing 5 Lea Numbers® on each page. Optotype size is 9.5M. Contrast levels are 25%, 10%, 5%, 2.5% and 1.25%. These flip charts can be used at several different distances. |