This is a keychain is 60mm x 50mm, and prints in about 35 minutes. Quick and easy print, and is durable at 2mm thick. I used the Hueforge program to generate the STL for this print, and it only uses 3 filament changes.

In the 3MF file you will see that I used a layer height modifier so that the base black layers are printed faster (at 0.2mm rather than 0.16). This is purely for efficiency. You can disregard it, and just print it at 0.08mm layer height the whole way through (except for the base at 0.16).

Print at 100% infill with a layer height of 0.08mm with a base layer of 0.16mm

Filaments Used:
- PLA Siddament Black Transmission Distance: 0.2
- PLA+ eSun Grey Transmission Distance: 1.4
- PLA META Sunlu White Transmission Distance: 9.6

Swap Instructions:
- Start with Black
- At layer #16 (1.36mm) swap to Grey
- At layer #17 (1.44mm) swap to White for the rest.