Ray-Ban Unisex RB3548N Hexagonal Sunglasses Imported Metal frame Plastic lens non-polarized Lens width: 51 millimeters Lens height: 45 millimeters Bridge: 21 millimeters Arm: 126 millimeters You have classic square aviators, you jumped on the round lens bandwagon and loved it so now you may be wondering what's next? The Ray-Ban&reg; Hexagonal Flat Lenses 51mm combines two iconic styles for a unique look that is sure to become a classic.