Bip39. Get the required range of COLDCARDs, choose Import Present throughout set up and cargo the same backup file on to each of them. Give Every COLDCARD its personal passphrase after which lock down the seed. Your seed words won't be recognised to any in the units and remain secure. https://onelifesocial.com/story4874334/bip39-https-linktr-ee-bip39-the-single-best-strategy-to-use-for-bip39-wallets