CooperVision Biomedics 55 premier aspheric contact lenses are designed to effectively control the average spherical aberration in the lens and human eye. Spherical aberration is the inability of a lens to focus light on a common point. That means Biomedics 55 premier contact lenses are able to focus light, providing you with clearer, crisper, sharper vision-regardless of the amount of correction required. At the same time, a rounded edge design provides excellent comfort.