Engineered Now Headrest for Herman Miller Aeron Chair H4 Remastered Graphite. An ergonomic headrest designed specifically for the Herman Miller Aeron chair (Remastered models from 2016 or older). This H4 size fits individuals 5 feet 11 inches or taller. Finished in Graphite color to complement Graphite Mesh, the headrest provides head and neck support with a free.