rio is a rounded style with stainless steel frames - creating an undeniably timeless design and lightweight construction, making this one a perfect choice for your everyday frames. rio was created to work with all face shapes. the making of the havana acetate is truly an artisanal process. first, monokel makes small colored pellets of various hues of yellow, brown and orange by mixing organic color powder with raw biodegradable cellulose acetate. the result is a highly durable, hypoallergenic material, made from renewable resources. the colored acetate pellets are then mixed and stirred by hand to achieve their speckled havana pattern, thus making the pattern on every frame unique - no two pairs alike. aviator pilots of the 1930s are often credited with making green lenses popular, choosing to wear them due to their ability to work in both sunny and low-light environments while reducing glare and brightening shadows. all of monokel's lenses feature anti-scratch and anti-reflective treatment with 100% uva/uvb protection. made by renowned german lens- and optics manufacturer carl zeiss. frame width: 137.3mm | frame height: 48.7mm | lens width: 46.3mm | nose width: 24.1mm | temple length: 145mm - reach-compliant stainless steel - 100% uv protective carl zeiss vision cr39 lenses - japanese 3-barrel obe stainless steel hinges - teflon covered hinge screws to prevent floppy arms - includes protective case, cleaning cloth and box for storage Rio Sunglasses - Gold