Contact Lens Base Curve

Base Curve, or BC, values range from about 8.0 to 9.5. The doctor fits the lens with the curvature most appropriate for your eye. Most disposable contact lenses come in several different base curve values. If your prescription does not contain a base curve value, this is likely because your brand of lens only comes in one base curve.
base curve values are a bit like clothes sizes - just because you are a base curve 8.6 in one brand of contact lenses doesn´t mean you will be in another.