V-Slot nut
thingiverse
I required this for an ongoing project of mine, possibly it could be beneficial to you as well.\r\nSimply insert a standard Chinese V-slot extrusion and allow the tapered end to protrude.
Download Model from thingiverse
With this file you will be able to print V-Slot nut 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 V-Slot nut.