During my end of the year cleaning I found an old atlas probe (mr3020). Was not connected for over a year now. I would like to give it back (or to somebody who actually uses it).
I know there is a “transfer ownership” button on the website. Is there anything I should pay attention to before giving the device to a total stranger? 
If you transfer your probe via that function, then the new host inherits everything - including your uptime history with all its details.
The alternative is that you send the probe back to us, we “refurbish” it meaning we give it a new identity and send it to someone else. In this case the new host will have no access yo the previous identity’s details.
The choice is yours - but either way, it is really nice to give the probe a new life!
Great. Which postal address should I use?
Btw: Sorry for hiding the device for so long.
I think it’s better to use the office address, and sub-address to the “RIPE Atlas team”
it is important to note that the specific terms and condition of return policies like proof of your purchase, condition of probe and check the warranty time may vary depending on the retailer or manufacturer, be sure to review the policy carefully before attempting to return your probe.
Probes can be purchased? Thats new to me.