How to identify, use, and replace the Copperhead Bowden coupler?
It's an embedded Bowden collet. Also called a Bowden clip which is a much more vague and overloeaded term.
E3D (UK) and MicroSwiss (US) have their own branded versions but they're likely not made in house, they're prbably reselling what they buy in.
Youtubers appear to pronounce this Bowden collect which does not help.