OLKB Part Changelog Planck PCBs rev 1 rev 2 breakout various pins rev 3 larger holes for Zealio switches rev 4 speaker added to C6 rev 5 mounting holes increased from 2.2mm to 2.85mm for Hi-Pro/EOTW cases rev 6 Complete redesign, upgrade to Arm USB Type-C 2x2u support No in-switch LEDs Speaker tied to two outputs Many footprints for addons rev 6.1 USB-C to USB-C bi-directionality fixed Sturdier 2u stabiliser holes Preonic PCBs rev 1 rev 2 mounting holes increased from 2.2mm to 2.85mm for Hi-Pro/EOTW cases rev 3 Complete redesign, upgrade to Arm USB Type-C 2x2u support No in-switch LEDs Speaker tied to two outputs Many footprints for addons