This is the "Project SI additional" template. It should be called in the following format:

{{Project SI additional
|SI domein=
|SI domein anders=
|SI activiteit=
|SI activiteit anders=
|Address=
|House number=
|Postal code=
|City=
|Contact=
|Phone=
|Mail=
|Hyperlink=
}}

Edit the page to see the template text.