ergonomic knuckles
thingiverse
This looks like a compact and well-designed American fist, engineered to fit comfortably in one's hand.
Download Model from thingiverse
With this file you will be able to print ergonomic knuckles 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 ergonomic knuckles.