A practical choice for buyers looking for the original headrest for the herman miller aeron chair (h3 for classic, carbon). The product headrests are offered in two sizes to accommodate a wide variety of users. If buyers are under 5′-11 (180 cm), choose the H3 model. If buyers are 5′-11 or taller, choose the H4 model. WHICH AERON DO buyers HAVE? 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). COLOR AND WEAVING – Classic Carbon – Color Code 3D01 – The Engineered Now Headrest perfectly matches your Aeron Chair in comfort, quality, color of frame and Mesh and the mesh weaving. Please make sure you choose the right Model and color of your chair, see it. 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. Headrest, Hex tool, Replacement Bolt for A-Size Chairs, Spare Cap. Recommended Uses For Product. Specific Uses For Product. Ergonomic, Neck Pain, Office. Package contents are based on the product information shown above. Please confirm compatibility, measurements, and required specifications before ordering. Your satisfaction is important to us, and we will work to resolve order issues promptly and fairly.