Put your Sigma speedometer on the desk when it's not at the bike, so you don't have to search for it anymore. ;) It's designed to be printed w/o supports.
Caveat: it may not fit for all Sigma models. I have a wireless BC 14.16 STS from 2020 and a BC 9.16 from 2021/22. — Do a test print of the twistlock first and also check for remixes that fit other models.
Printed in PLA with front side (speedometer mount) facing upwards, no supports except for the twistlock, 0.4 mm nozzle, 0.2 mm layer height, arachne, lightning infill.

The author marked this model as their own original creation.