Adding own extra html tags like <TEST />

Hello everyone here,

thanks for this great tool and your help here

We would like to use the CKEditor in our CMS. It looks great, but i have one question:

We have several own html tags, all like this <TAG1 />, <BLAH /> to call specific site elements like a video or something like that.

In my tests, CKEditor, when i insert this tags in HTML Mode, changes them to like <tag> </tag>, then of course the tags dont work anymore. Is there a way to changes this? Or can we even add these tags as a button in the editor?

Thanks for your help,

Greets