> For the complete documentation index, see [llms.txt](https://enterprise.hideez.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://enterprise.hideez.com/hideez-enterprise-server/hardware-vaults/how-to-add-an-rfid-code-to-the-employee-key.md).

# How to see an RFID code on the Employee key?

Every Hideez Key comes with RFID module and a unique code that has already been put in Em-Marine standard.

It can be used as [key for physical doors](/hideez-key-enterprise-edition/key-for-physical-doors.md) .

You must register the RFID code on the key.\
Please see the video how you can replace existing code on Hideez Key.

{% embed url="<https://www.youtube.com/watch?v=Y_TOqRDpxAk>" %}

If you can use existing code and write it to other systems, for example your Access Control System, you need to know it.