Samsung is in the midst of a massive Galaxy Note 7 recall, but, with millions of devices on the market, some units are bound to fall through the net. Many owners – like that Florida man whose car was totaled in a fire – don’t even know they’re supposed to get their device replaced.

So, how can you tell whether a Note 7 is safe to use or is one from the original batch with a potentially faulty battery?

Samsung Australia has published new information on the recall process that sheds some light on the issue.

New Note 7 units will feature a couple of distinctive marks on their retail box. Look for a “small black square on the white barcode” and a round sticker with the letter “S”. We marked them with red in this picture:

What if you don’t have the retail box for some reason? You will still be able to check if a Note 7 is safe by running its IMEI number through a Samsung website. This online database will go live once replacement units become available. In Australia, that will be from September 21.

You can take the phone’s unique IMEI number from its packaging (if available), or from the phone’s back, or from the device settings, by going to Settings > General > Status.

Even if the device box has the black square and “S” sticker, it’s probably best to run the IMEI number taken from the phone through Samsung’s database anyway, just to be extra sure.

We expect the markings to be similar in other markets. Samsung said it would begin the worldwide Note 7 recall process from around the middle of September.

If you happen to run into a Note 7 unit from the original batch, don’t take any chances and go through the recall process – the small nuisance is definitely worth the peace of mind of knowing your device won’t just set itself aflame without warning.