Blank foam finger
thingiverse
Those large holes are similar, but tailored specifically for fingers. The diameter of this hole is 16 millimeters.
Download Model from thingiverse
With this file you will be able to print Blank foam finger 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 Blank foam finger.