Bip39 Checksum. Have the required number of COLDCARDs, pick Import Existing during set up and load the same backup file onto Each and every of them. Give Each individual COLDCARD its possess passphrase and then lock down the seed. Your seed words won't be known to any in the devices https://meshbookmarks.com/story18697747/bip39-word-list-https-linktr-ee-bip39-getting-my-bip39-wallets-to-work