Two way screw with dual threaded nut, various sizes

This is a remix of a remix from AdapWP (on Thingiverse). 

It adds a hex pattern which makes turning it easier and adds some weight to the nuts. 

I've also added various different lengths of the screw. 

The screw is dual-threaded so both clockwise and counter-clockwise nuts will work on it. Best of all, the dual-threaded nut can turn both directions. 

It's super fun to fidget with, and a good test of your printer's tolerances. If printed properly, the weight of the nuts is enough for them to slide on their own.