Customizable key tag
thingiverse
Classic design. It can be attached to a key ring. The examples from the picture have been printed of PLA using a slightly modded Anet A8. You can customize several parameters, i.e. label, level of corner roundness, thickness, etc. The default values seems reasonable, though.
Download Model from thingiverse
With this file you will be able to print Customizable key tag with your 3D printer. Click on the button and save the file on your computer to work, edit or customize your design. You can also find more 3D designs for printers on Customizable key tag.