Dray SilverDray Silver Unisex Shape. Frame Color: Silver Lens Color: Black 2 Year Warranty Technical Information: Hand Polished. Width Nose Gap Height Measurements of this pair: 145 20 55 mm Hinge: Five barrel Lenses: Base 2 Front thickness: 4. 8 mm Temples thickness: 3. 5 mm Lenses Technology: CR 39 Custom Made Lenses CR 39 is made by polymerization of diethyleneglycol bis allylcarbonate (ADC) in presence of diisopropyl peroxydicarbonate (IPP) initiator. "CR