Foldable shades from the '70s

Bringing back late-70's French design, these sunnies come in the black, blue, or clear, round-lens Sports model, as well as the black/tortoise shell Sunpocket II, with a subtly higher bridge and tapered lenses; each folds into the footprint of a single lens, and stores neatly in a clamshell hardcase, which can be conveniently forgotten in the place where you use your oyster card.