It's not actually a “card”. [Coldcard](https://www.ballet.com/en/) is a digital device... it looks like a calculator.  

But there are wallets with a form-factor that looks more like a credit card... [Cool Wallet](https://www.ballet.com/en/) and [Arculus](https://www.ballet.com/en/), for example. There is also [Ballet Wallet](https://www.ballet.com/en/) and you can make your own [paper wallet](https://www.bitcoin.com/get-started/setting-up-your-own-cold-storage-bitcoin-wallet/), which I'd only recommend if you know what you're doing. 

SatoshiNakanodo

bitcoin

What's the last thing you bought with BTC or Lightning in November?

mikhael

The private key on a card idea seems neat