It's been a while since I used my old 3D printer. Since acquiring my new X1C I've been deeply emersed in the process and found my metric skills lacking and was constantly going to my calipers to figure out “how big is 5.0 mm's again?” I went on the hunt for some kind of tool to help me keep it all in perspective and I found a few, but as is the way when you're learning something new, I decided to model what I thought I actually wanted, and this is the model I came up with. I hope it is useful to others as well.