I love these B&L Ray-Ban aviator sunglasses... I have been wearing them since about 1973, and I have found that the 58mm size is best for me! The reason I love them so much is that they are very effective at protecting my eyes when riding motorcycles. However, I have bifocal prescriptions now, so I buy the sunglasses just to get the frames and have clear prescription lenses cut to fit them. I cannot get B&L prescription sunglasses lenses made in the green because B&L does not make bifocal blanks, only progressive. So, I just use good quality clip-ons over the prescription lenses.