badBrick Worm, and Tree Gear Set.

Worm Gear. and 24 Tooth "Tree Top" Gears. Lego Technic compatible. ( Don't know what else to call them.)

These are 2 of the full kit over at http://www.badbrick.com
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In our 3D catalog under Gears.
Didn't want to double post a bunch of gears.