Hi @noclueat, welcome to our forum! All you need to return is the experiabox and if you also have a TV subscription the set-top box and their respective power adapters.
The NT or FTU is part of the fiber installation and is supposed to stay! (including it's power adapter)
You'll receive a letter with a return-box to send all of this back.
If you havent received the box or that's taking too long you can also use our free return adress and any regular box.
Return adress:
Kpn
Antwoordnummer 10119
2400VB Alphen aan den Rijn
*edit: updated reply
Tv box and router come with powersupplies. You can also send these back. The powersupplie which is connected tot the NT or FTU must NOT be sent.
Thank you both for your reply.
I just found below link with some instructions. It says I can send by PostNL in below address, is this correct?
Return address:
Kpn
Antwoordnummer 10119
2400VB Alphen aan den Rijn
https://www.kpn.com/service/administratie/terugsturen.htm#/ser-terugsturen/ser-terugsturen-huur-bruikleen-opzeggen-annuleren
You should receive a box from KPN.