Straight Edge PD Ruler Pupillary Distance Rulers

✡ The PD ruler can help you when you want to buy glasses online.
✡ Come With 4 different types of rulers which suit different needs, and 3 types are soft rulers, and 1 type are hard rulers.
✡ Put the notch over your nose, as close to your eyes as you can, then find the middle of your pupils in a mirror, < br//> Read the line closest to the middle of the pupils.
✡ This measuring ruler is easy to use, so you can buy glasses that suit to you online.