Print from flexible material (other materials might not endure the stress), infill at least 30%, print at 101-105% size so it´s easier to put them on wheels :)
After heavy use or any practise, check for any cracks or so. If you break one or two, nothing should happen (the other 2 will prevent you from rolling). Always use 4 at the same time.
Hope you like it, if you land any sick tricks share below ;)
(variants include: 48mm , 52mm, 56mm, 60mm in diameter)
The author hasn't provided the model origin yet.