This is a Herman Miller Classic Aeron, labeled as #C13. This chair is a size C model, it has been refurbished to excellent condition. #C13 has been thoroughly tested, and is 100% mechanically functional. Chair has been refurbished and upgraded with/ Forward & backward tilt, added an adjustable lumbar, thumbwheel adjustable arms, replaced damaged arm rest, and replaced pneumatic cylinder with a new one. Aeron headrest for 60. New Hardwood Floor castors for 20. Please inspect every picture thoroughly, zoom in, zoom out, & don’t hesitate to ask any questions about the chair you are looking at. Because what you see is what you will get. Installation Video: Backrest will need to installed. Installation video on YouTube will be available, via shared link, upon request.