Introduction to SafeCards
GridPlus SafeCards allow users to securely back up their seeds onto PIN protected cards which can also function as additional wallets. Every SafeCard is essentially a physical carrier of a HD wallet seed that looks like a traditional credit/debit card.
We believe you should take all precautions to protect your funds and prevent someone from getting their hands on your private keys - and one form of an attack that's not talked about often is what we call the "sock drawer" attack, i.e. when someone leaves their written seed phrase in the bottom of their sock drawer and someone else finds it. People inadvertently introduce risk with how they store their seed phrase - cloud storage is a big problem in this area.
This is why we decided to use the PIN protected SafeCards to store/backup your wallets - if someone finds your backup, they still can't use it without the PIN, which adds another layer of security on top of everything else (but if you want to back up with a seed phrase, you still have the option of course).
When you buy a Lattice1, you will receive one SafeCard in a bundle with the device.
When inserted into the Lattice1, the Safe Card “takes over” as the default wallet of the device. This means that any signatures requests are done so on keys held in the card (rather than the device itself). When removed, the SafeCard can no longer make signatures, so the device’s built-in Lattice1 wallet (the chip of this wallet is exactly the same as a SafeCard chip) returns as the default wallet.
Security is ensured by a certificate that only GridPlus can provide - if the cert is not detected in an inserted card, the Lattice1 will simply not communicate with the card. And since only valid SafeCards with a GridPlus certificate can be used with the device, there is no way to attack it through the card slot. Read more about the SafeCard concept in this blog post by our CTO Alex:
Check this article for more information on how to setup your new SafeCard: