Some t5 idler pulleys.
Both 19 and 20 teeth versions.
The 20 teeth variety also has a deep grove version.
The pulley teeth are printing much more rounded than the CAD file on my printer.
This is part of my Baby-Huey large format 3D printer project.
nerdipedia.com/tiki-index.php?page=huey
It may also be of use for other projects.