The Herman Miller Aeron Graphite Medium Size B Replacement Seat Frame is a high-quality office/desk chair designed specifically for the Herman Miller Aeron model. It was taken off a damaged chair. Seat is still usable, no cracks in the frame, but the mesh has some damage. New mesh could be added if you want. This way you know you have all the screws if you decide to replace the mesh. If you do replace the seat, you know you have all the hardware for the replacement.