These are for testing the visual acuity of very young children from the age of around 2 years old. The child is asked to name a selection of pictures from the flip-over book and the smallest recognisable picture is recorded. The results are reliable as the 22 pictures are designed and graded in the same way as Snellen letters and correlate to Snellen acuity. The visual range is 3/30 to 3/3 and a near vision card is included for use at 33cm. A choice of 3 or 4 different pictures exists at each acuity size. Recognition books are provided to help familiarise very young or shy children with all 22 pictures before testing begins, or even at home.