I needed some replacement hoops for some JEM wireless earbuds (specifically the HXEP400B set) and could not find replacements that fit. So i made em.
might have to scale up/down for your specific printer but it prints good on my Anet
I printed at 40% infill for more strength, but you can go pretty low. .15mil layer height seemed to work best with my .3mil nozzle
The author hasn't provided the model origin yet.