The Dharma Wheel or Dharmachakra in Sanskrit - keychain.

Dimensions: 35 mm diameter 3 mm height

Print time is more or less around 21m at 0.16 layer heigh (0.4 mm nozzle).
Print time is more or less around 28m at 0.12 layer heigh (0.4 mm nozzle).

Print parameters:

Layer height - 0.16 mm or 0.12 mm
Perimeters - 3
Infill - 10%
Brim - NO 
Support - NO
Raft - NO
Filament type - PLA or any

Could be printed in multicolor without MMU, AMS or similar.

For multicolor print:

When printing at 0.16 layer height: put the printer in Color Change mode(G-code M600) at layer 15 and then change filament
When printing at 0.12 layer height: put the printer in Color Change mode(G-code M600) at layer 20 and then change filament