You should choose a Legacy backup for an Unchained vault. Avoid the 20-word single/multi-share backup types.
Trezor hardware wallets, particularly the Trezor Safe 3 and Trezor Safe 5, offer choices regarding the type of backup you can use.
The most common backup type is a standard seed phrase, which is 12 or 24 words. Trezor calls this the "Legacy backup." We recommend choosing this option for your Trezor, because it's the most interoperable with other hardware wallets. It gives you the option to easily migrate to a different brand of Unchained-supported hardware wallet, rather than being reliant on Trezor as a manufacturer.
Learn: The other types of backups are related to Shamir's secret sharing, an alternative to multisig. We have an article that discusses the tradeoffs between the two options.
How to choose the correct option
- During the setup of your Trezor, when you get to the Create new wallet screen, choose the down arrow.
- Next, look for the Legacy backup types. Ensure that either 12-word Backup (recommended) or 24-word Backup is selected. There is not a practical security difference between 12 or 24 words, but 12 words are easier to write down and store.
- That's it! You can continue with setting up your Trezor.