TIL about "plug-in power", that seems to be a thing that some sound recording devices with 3.5 mm "phono" jacks can provide.

Here [1] is a page at Klover, and here [2] is one at Shure. Not sure if there's a formal specification for this, or if it's just something that manufacturers started doing.

[1]: https://www.kloverproducts.com/blog/what-is-plugin-power

[2]: https://service.shure.com/s/article/difference-between-bias-...