These are soft jaws to suit 3" vices. They have internal ridges which should help them to fit snugly, but there are also a couple of recesses to suit 8x1mm magnets if you need them. They have handy slots which are useful for cutting rod, tube etc.

These print easily without supports (best oriented with the flat internal face towards the bed).

This is kind of a remix of my previous 4" vice design, which is still available here:
https://www.thingiverse.com/thing:2990072

Anycubic Kossel Delta

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