The Ray-Ban RB3548N Hexagonal is sold in three aftermarket eye sizes — 48mm, 51mm, and 54mm — all cut for its irregular metal front and 145mm metal arms on a unisex build. That irregular hexagonal shape is the outlier in this catalog, where square, round, and aviator fronts make up most of the range, so check the size carefully since none of the three share a lens.

An irregular shape like the hexagon has more lens edge exposed at odd angles than a square or round front does, so fit tolerance matters more on the RB3548N than on a simpler shape — a lens cut even slightly off the frame's true geometry shows at the corners first. Because the shape itself is already a style statement, plain solid tints are a common choice here over a mirror finish that competes with the frame's outline.