Herman Miller Aeron Headrest Adapter

The original headrest costs ~$150, which is a bit much for me. So I started looking for alternatives, but none of them could be mounted on the chair without significant design changes, and the existing mounts did not work because of the shape of the top of the backrest.
When I got a 3D printer, I looked again for a solution to this problem, but I didn't like the options I found or they didn't work well. So I made my own version of the adapter for third party headrests that have a 65mm distance between the mounting holes.
The 2 versions of headrests I have work perfectly with this adapter. You will need 3 M4x18 bolts and 3 nuts.
The ones I bought are no longer available, but these look similar and probably you could find some by searching for "adjustable headrest for office chair".

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