These are soft jaws for a 4" vice. They cover the existing steel jaws which measure 4 1/2" by 3/4" (or 115mm by 20mm). They have cutouts for holding round objects and for better grip.

No screws, magnets, or other fasteners are required; it simply slides on over the existing steel jaws.

I recommend printing in TPU at relatively high infill. PLA will work, but the jaws will be more likely to mar objects than with using a more flexible filament. Obviously you will need to print two to make a set.

If you have interest in these jaws for a different size vice, feel free to message me with the specifications.