You can back up the NGRAVE key on the GRAPHENE backup plates.
If you do not own a GRAPHENE you can choose to back up your key on a piece of paper, but this is less durable and not the recommended approach.
You can back up the NGRAVE key on the GRAPHENE backup plates.
If you do not own a GRAPHENE you can choose to back up your key on a piece of paper, but this is less durable and not the recommended approach.