The Ray-Ban RB3506 takes a 64mm lens, one of the larger aftermarket sizes in this catalog, built for its oval plastic front and 135mm plastic arms. Oval fronts this size are less common than the square or round shapes that dominate the rest of the range, so double-check the 64mm figure against the lens you're replacing before ordering, since a smaller cut will sit loose in the channel.

Larger oval lenses like this one are usually chosen for broader glare coverage rather than for a fashion statement, which is why gradient and grey solid tints are the more practical picks over a full mirror — a 64mm mirrored lens throws a lot more reflection than a 55mm one does, and that extra surface area is also why the plastic front needs a full 135mm arm to balance it.