How do I know which size Aeron I have?
The Aeron chair comes in three sizes: A, B and C (smallest to largest). You can easily determine which size you have by feeling for one, two or three bumps located under the flange on the top/back of the chair, right at the centre. Place your hand up and between the flange and the mesh to locate the bumps. One bump = Size A, two bumps = Size B and three bumps = Size C.