Engineered Now The Original Headrest For The Herman Miller Aeron Chair H3 For. Please be sure to select the correct’Size’. H3 – For individuals under 5’11” (Under 180cm) H4 – For individuals 5’11” or taller (Over 180cm). ONYX COLOR – Color Code 23105 – Perfectly matches your Remastered Aeron Chair in comfort, quality, and color, with complementary Onyx Mesh. [MATCHES REMASTERED AERON CHAIR MODELS YEAR 2016 OR OLDER]. Headrest only; CHAIR NOT INCLUDED. ERGONOMIC DESIGN – Provides head and neck support to help maintain comfort and alignment during long sitting sessions. Designed for ergonomic performance. Free-Floating System – Tilt and height adjustments move freely. Forward and backward angles can be locked for a custom fit and lasting comfort. H3 – For individuals under 5’11” (Under 180cm) H4 – For individuals 5’11” or taller (Over 180cm), ONYX COLOR – Color Code 23105 – Perfectly matches your Remastered Aeron Chair in comfort, quality, and color, with complementary Onyx Mesh.