Requires both "inside" and "outside" parts.

Install the outer part into your wall first, like a simple pass-thru grommet.
Then, slide the inner sleeve onto your cable and push it into the outer grommet.

The inner sleeve can be rotated to adjust the bend of the cable.

FlashForge

Adventurer 5M

No

No

No supports are needed with the face of the grommets against the bed.

TinkerCad -> exported to Fusion for fillets