Oakley X Squared is probably the most durable pair of sunglasses. The lenses are made with Oakley HYDROPHOBIC/Oleophobic technology, a performance coating that lets water slide off to help keep your vision clear. It also fights smudges from skin oils and lotions, and it even repels dust. Meanwhile, the frame is made out of lightweight titanium and uses “flex-couplers” that precisely adjusts the fit of the frame around your head. $350.