The 10 line test is used for screening 3 to 5 year olds, measures 15 1/2" x 17 1/2" and folds to 8 1/2" x 17". Includes a hole for hanging. The 15 line test can be used to screen 5 year olds and older, measures 17" x 22" and folds to 11" x 17". Has a hole for hanging and three sets of symbols on lower lines to avoid memorization.