The Tifosi Optics Elder Interchangeable Sunglasses have enough wisdom to know that you need different tints when you're running in different times of the day. That's why you can switch lenses quickly, and Tifosi included three different pairs of lenses with different tints. Tifosi made the lenses out of scratch resistant, shatterproof polycarbonate, and treated the lenses with a hydrophilic coating to repel rain and sweat. The lenses also features ventilation slits for airflow, a Glare Guard to deflect reflection, and an optically decentered design to eliminate distortion. Grilamid TR90 makes the Elder's frame flexible, superlight, and surprisingly strong, and there are adjustable nose pads for a secure grip. Proposition 65 Warning for California Consumers: This product contains chemicals known to the State of California to cause cancer andor birth defects or other reproductive harm.