Oakley - BXTR Metal pays homage to Baxter Street, a popular skate spot in Los Angeles where style and authenticity are always on display, just like this frame. The shield sunglass was developed by Oakleys team of designers who collaborated closely with friends of the brand to uncover a unique take on lifestyle eyewear. BXTR Metals modernized trigger stem is inspired by Oakleys original Razor Blade sunglasses. The frame is elevated with metal material in homage to the prototype for the first Oakley sunglass made from a goggle lens and wire coat hanger. The BiO-Matter* frame material means all-day comfort and lightweight durability, while Unobtainium nosepads provide increased grip. *BiO-Matter is made from bio-materials having at least 56% bio-based carbon content (representing ratio of castor oil to fossil sources). Category 3. General purpose sunglasses. High protection against sunglare, good UV protection, not suitable for driving at twilight, at night or under dull light.