Exceeding the standards of world champion watersport athletes, the Heritage Series features Hobie's highest quality, thin, lightweight and durable Borosilicate Glass lenses with Hydroclean Plus™ Polarized lens technology. Lenses are set in carefully crafted frames of Grilamid TR-90. The Heritage Series also features precision flex hinges for a custom fit and extra durability on some models. Megol nose pads and Megol temple tips are available on some models, as well. Each style has been carefully rated by size, with measurements, in an effort to assist you in making informed purchasing decisions. Hobie Polarized frames are all backed by their Friendly Lifetime Warranty.