Customizable hexagonal nut cover
thingiverse
This generates a customisable hexagonal nut cover, where you can not only set the dimensions of the nut but also fiddle the curve so you can generate a low profile nut cover. Everything else I saw was too knobby for my purposes.
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With this file you will be able to print Customizable hexagonal nut cover 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 hexagonal nut cover.