Enjoy auto-adjusting sub-protection with the Zeal Optics Sable Sunglasses. Featuring medium-fit frames, the impact-resistant Sable now includes an Auto-Sun feature. It's lenses shift from low-light bright yellow with a 28% Visual Light Transmission (VLT) to a high-visibility persimmon with a 15% VLT in bright sunlight. The Sable also incorporates plant-based materials with its Z-Resin Bio-Plastic frame, fabricated from natural castor bean oils. Its Ellume Bio-Plastic Lens integrates plant-based bonding materials while providing 99.9% polarization and 100% protection from UVA/B and UVC rays.