these are custom slack spacers for BMX freecoaster hubs as the fit OEM and KHE-Style clones.
they have a 19.5 mm inner diameter and 27mm outer diameter,
each spacer is 1 mm thick,allowing you to stack to fine-tune your slack-test with different combinations to get the engagement feel you want.
tip: once you've found your perfect slack amount, you can combine multiple spacer or change the z perimeter on your slicer file and print a solid single-piece version
i personally like 5.5 mm tick
The author marked this model as their own original creation.