ABOUT THIS ITEM (WE AIM TO SHOW YOU ACCURATE PRODUCT INFORMATION): 1. PLEASE SEE THE SIZE REFERENCE TO FIND THE CORRECT SIZE. 2. LIGHT MAY CAUSE SLIGHT CHROMATIC ABERRATION. 3. PLEASE ALLOW 1-3CM DIFFERENCE DUE TO MANUAL MEASUREMENT (NOTE 1CM=0.39INCH). THANKS FOR YOUR UNDERSTANDING!