Wall-mounted key hanger. It's expandable to your needs. The keys can be stored on it with key rings or with small pins on the rings. The pins might be tagged. The fitting pins are included in the .stl files.

The fitting was tuned to Onix PRO410 on Sonic 4K printer. It's worth printing small sections to check and adjust if needed as fitting is quite tight.

The holders are fitted with small holes should you attach small signs or marks for the keys. The signs with the small pins are not included in this design.