I took some inspiration on the original Brompton Easy Wheels, and also on other models I saw around the web, but designed this one from scratch.
They are intended to be instaled using the original parts on the standard roller (12mm tube, shim and screw)
If you want to print yours for free, you can download it from MarkerWorld: https://makerworld.com/en/models/2210723-brompton-3-part-easy-wheels#profileId-2403209
by barrasman