We recommend to chose the Diameter of the lens by adding 2.00 mm to the HVID.
Diameter 13.00 mm = flattest K + 0.50 mm
Diameter 13.50 mm = flattest K + 0.70 mm
Diameter 14.00 mm = flattest K + 0.90 mm
Diameter 14.50 mm = flattest K + 1.10 mm
Diameter 15.00 mm = flattest K + 1.30 mm
Correct distance with as much plus as possible and add additionally:
+0.50 dpt for hyperopia
+0.25 dpt for myopia
A, B and C covering a range of additions from +0.50D to +2.75D
Choose the add based on the required reading addition and age to ensure the optimum Progressive Power Profile for visual requirements and pupil size.