Lea Numbers Single Number Book for use at 10 Feet (3 M). Ideal for situations in which the child/adult cannot perform when tested with a line test. This book can help determine the best resolution of the visual pathway in a child or adult with amblyopia or impaired vision. Includes isolating mask and instructions. 13 pages, 5in x 5in (12.7 cm x 12.7 cm)
