Coinkite
MicroSD (air-gapped), USB-C, NFC
OLED 128×64
Bitcoin only
2022
$157.94
The Coldcard Mk4 is the fourth generation of Coinkite's security-focused Bitcoin-only hardware wallet. It features two secure element chips, NFC for tap-to-sign (optional), USB-C, MicroSD for air-gapped transactions, a full numeric keypad, and multiple security features including duress PINs, brick-me PINs, and countdown login. The Mk4 is considered one of the most secure hardware wallets available.