Herman Miller Aeron Chair Highly Adjustable with Lumbar Support Pad with Translucent H9 Hard Floor Casters - Large Size (C) Titanium Smoke Light Frame, Classic Zinc Pellicle Mesh Home Office Desk Task Chair The 12-Year Warranty covers everything that makes a Herman Miller Office Chair--including casters, tilts, pneumatic cylinders, and all moving mechanisms. Genuine Highly Adjustable Aeron with Lumbar Support Pad with Translucent H9 Hard Floor Casters - Large Size C - Titanium Smoke Frame Adjustable Padded Arms, Forward Tilt, Tilt Limiter The Aeron chair by Herman Miller is, simply put, the best ergonomic chair you can buy.