These along with your version of the spool has made my life easier. My ToM is printing without me having to keep an eye on whether the filament is feeding correctly. I plan to use these also with a 1kg spool hanger (http://www.thingiverse.com/thing:10463)http://www.thingiverse.com/thi... for the filament I get on spools since these make for such a smooth transition. It mounts on the side, so I will just print another bottom guide to go on that side to bring the filament around to the existing guides. Thanks for your work on these.