There's four or five charge cords with adapters laying around here, and losing the adapter is always a concern. So I've been wanting to make these connectors for a while.

The filament is rubbery 95A TPU. The Micro adapters in the photo are actually smaller than the cords' USB-C ends, but one size stretches to fit all. And resizing these to fit whatever needs it, is entirely possible. A percent or two in length might be right.

Four took 20 minutes using Orca Slicer's generic TPU filament... The only adjustment I made was adding a little 2 mm outer brim, because these have a small footprint. And even with zero gap, the brims pulled right off.