First, I'd like to preface that I am new to crypto currency. My plan is to put 1 BTC on one of these offline cards and not touch it for 5-10 years.
https://www.balletcrypto.com/en/
In essence, it is an offline cold storage stainless steel credit card like device that has both the private encrypted key and wallet passphrase written/etched onto the card itself. Many would consider that highly unethical/unsecure in the crypto world.
The biggest question I have is - can Bobby Lee and his company be trusted? Are the keys/passphrases generated really destroyed/lost forever after his company generates them?
If the answer is YES, then essentially you are holding your own crypto bank account in your hands with zero backup. Lose the card, and you lose your crypto currency. Bobby and his company seem to be marketing this as a first-step to introducing crypto currency to the mass market. He has said on several occasions that he views this as more of a gift card type production and not a "dump all your money onto this card" adventure.
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PS - Bobby's new company Ballet Crypto operates under Mintery Inc, registered in Las Vegas as a Delaware Foreign Corporation. He is a pioneer in the crypto world, recently selling off China's first, and once the world's largest, bitcoin exchange company BTCChina. Bobby's brother Charlie is the creator of the crypto currency Litecoin. Bobby has formerly worked for Yahoo and Walmart China, while Charlie is a former employee of Google and Coinbase.