2 sizes of t-nuts, fit for M3 nuts.

designed for V-slot aluminum rails,
The small one is for 20mm rails, the large one is for 30mm rails

Asiga Max X35

No

No

Full

No need for supports, just print the T-nut on it's side.
it's a very small print and it's under a lot of stress, so its preferred to print with 100% infill.
It will probably work with less infill, but it's not a big difference.