Central horizontal and vertical resolution gratings. Charts are supplied with AcuFlect 3 media which, while less reflective than the original AcuFlect Glossy, still maintains the dynamic range and color saturation that have made the original charts legendary. What does this mean to you? It means that setting up the charts will be easier under multiple different light sources, therefore saving you time. The AcuFlect 3 surface can be wiped down with a damp cloth and has the added benefit of being more Eco-friendly.