How To Measure Your PD (Pupil Distance)
Step 1.
Stand facing a mirror, at a distance of about 20cms.
Step 2.
Keep your head straight and hold the ruler against your forehead/eyebrows.
Step 3.
Close your right eye and align the '0' with to the center of your left pupil. (middle of black circular bit of your eye).
Step 4.
Without moving the ruler, close your left eye now, and open your right eye.
Final Step.
Now read the MM measurement that lines up with the center of your right pupil. Please record that number. It is usually between 57mm to 69mm.