Its a bracket to attach holders for a hotend nozzles and spare scraper blades it fits right below the tool holder on the spool side and mine attached using stock screws. I do have a 10mm spacer on mine tho so yours most likely will fit.
The author remixed this model.
Widened the base to fit the Elegoo Centauri Carbon printable scraper blades
Attached and inverted the Nozzle holder reorientated it to fit the adapter bracket
Used a modification of the CC Hotend Holder.