QMK Proton C
Developed by the QMK collaborators, the Proton C allows you to upgrade any Pro Micro compatible keyboard kit to take advantage of a robust USB Type-C port, a faster Arm chipset, and an optional speaker. Extra pins are availble on the lower half of the Proton C, and can be broken off for builds that aren't compatible.
Includes a 5V step-up output for WS2812 LED chains (rest of board is 3.3V), and a reset button to put the MCU into the bootloader mode.
$2 of every sale goes to QMK.