4 Pack PD Ruler Optical Vernier Pupilary Ruler Distance Meter Ophthalmic Tool

Description

4 Pack PD Ruler Optical Vernier Pupilary Ruler Distance Meter Ophthalmic Tool
Feature:
The pd ruler can help you when you want to buy glasses online
Put the notch over your nose, as close to your eyes as you can, then find the middle if your pupils in a mirror,
read the line closest to the middle of the pupils.
Come With 4 different types rulers which suits different need,
and 3 types are soft rulers , and 1 type are hard rulers.
Note
that this does not come with any instructions,
so if you don't know how to take a PD measurement, you will need to look that up on the internet.
Material: Plastic,
Length (mm):180/7"
Width(mm):25/1",
Quantity: 4PCS.