These fun colorful and easy to use pediatric rulers will help your opticians fit the littlest of your patients with ease. They feature easy and quick-to-read numbers for the busiest kiddos who won’t sit still for but a moment. The unique see-through windows will not obstruct the child’s vision, allowing them to feel more comfortable while being measured. It just takes a quick game of peek-a-boo and occluding for your optician to obtain an accurate monocular pupillary distance.