Titanium sunglasses have interchangeable lenses.

Porsche Design is bringing back the racing-inspired sunglasses that were first launched in 1978 and became famous after being worn by Paul Newman and Tom Selleck as Magnum P.I., Maxim writes. The new Porsche Design P’8678 sunglass model, the article says, is crafted of titanium and features interchangeable lenses. “During the design process, expertise from Porsche Design Timepieces AG, based in Solothurn, Switzerland, was applied to the replaceable lens locking mechanism, which allows a comfortable, quick, and safe replacement of the lenses and hence an easy adaptation to different light conditions.”

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