After some feedback from my previously uploaded Keyring Caliper I have decided to make some changes. I have uploaded this as a second option because while I believe the changes create a more functional product, some people still may prefer option 1. 

I have redesigned the components so that the body can be printed flat on its back. This creates a very smooth sliding motion between the parts and makes the keyring loop considerably stronger. 

This caliper still achieves my original goal of having something small and pocketable that can be used for quick measurements. If you would like to see the original version it is posted here:

[https://makerworld.com/en/models/1041801-keyring-caliper](https://makerworld.com/en/models/1041801-keyring-caliper)