From https://lectronz.com:

The AIOC is a small adapter with a USB-C connector that enumerates itself as a sound-card (e.g. for APRS purposes), a virtual tty (“COM Port”) for programming and asserting the PTT (Push-To-Talk) as well as a CM108 compatible HID endpoint for CM108-style PTT (new in firmware version 1.2.0).

The AIOC is Open-Source Hardware designed by Simon Küppers.