The file 'Two Winged Thumbscrew / Nut Adapter 3D Printer Model' is (stl) file type, size is 252.6KB.
I use this to tighten the nut on a RAM mounting arm. All the "wheel" style ones I could find were a little sharp and therefor painful to turn tightly. This one has rounded corners and is easy to crank down on.
It fits a standard 7/16 nut with a friction fit. The exact inner diameter of the hex hole is 10.9mm.
two-winged_thumb_screw.stl | 563.5KB |