If you are worried about the warranty for your Leap I would do this but what I did was this:
Bought this - https://www.amazon.com/dp/B00YE30HT8/ref=cm_sw_r_apan_glt_i_HYD4GWAK1ZBDXJE637YC?_encoding=UTF8&psc=1
Drilled some holes in the plastic back, added a metal reinforcement plate (probably not needed) on the inside part of the seat that the headrest bolts through along with the plastic. The results are pretty good.
Big fan of the Fern and my favorite when compared with the Aeron or Leap V2 which I've also owned. Wish it came with a headrest but I plan on strapping a $20 Lorell one somehow to bring it all together.
Lorell 86000 Series Exec Chair Adjustable Headrest Head Rest, 6 x 12.6 x 1.6, Black https://www.amazon.com/dp/B00YE30HT8/ref=cm_sw_r_cp_api_glt_fabc_C7F91BMFXQG9T0XEQ5E8?_encoding=UTF8&psc=1
This is the one I used!
Yes, this is what I got with some bracket holders. Works great if you’re taller. Lorell 86000 Series Exec Chair... https://www.amazon.com/dp/B00YE30HT8?ref=ppx_pop_mob_ap_share
You can use below
Lorell 86000 Series Exec Chair Adjustable Headrest + SmallRig Super Clamp or CAMVATE Universal C-Clamp for
Check the image reviews maybe you can get an idea
Hi, I just bought a leap and I'm waiting for it to arrive. Also from Canada! So do you think you would recommend this version of the headrest that some other people in this thread seemed to use? https://www.amazon.ca/Lorell-LLR60329-Executive-Adjustable-Headrest/dp/B00YE30HT8/ref=sr_1_2?dchild=1&keywords=lorell+headrest&qid=1611863934&sr=8-2
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It seems like it might be a bit less invasive. Also, I believe that it uses the exact same attachment, so you might be able to buy this one and replace it with the one you have in the exact same drilled holes. Edit: FYI, I am 5 foot 11 inches.
I have found a solution that I am going to try out for myself and will post the results here if you would like.
Basically you can buy a generic headrest that screws into an office chair but obviously we wouldn't want to do that to a nice chair like the Leap. So you can get a pair of C Clamps with it that fit the same size as the screws for the headrest and use those to attach it to your chair.
The only concerns I have are that it will be too far back to actually offer any head/neck support but I think I could figure out a way to adjust it somehow.
Here's the products I'm ordering from Amazon (Canada)
https://www.amazon.ca/gp/product/B00YE30HT8/ref=ox_sc_act_title_1?smid=A2T3CA2GEPZF2K&psc=1