This is a simple test wheel in the form of a PUZZLE.
It will check both color changes, of which there are 176 (valid for 8 different colors), as well as X and Y axis calibration.
The puzzle is functional after printing and the model can be disassembled (my daughter likes to assemble PUZZLES)

Printed from PLA Polyterra, they have very nice shades and colors, but can be printed from any AMS compatible material.