CoinkiteDiscontinued Open Source USB
Coldcard Mk3
Brand
Coinkite
Connectivity
MicroSD (air-gapped), USB Micro-B
Display
OLED 128×64
Supported Coins
Bitcoin only
Released
2019
Price
Discontinued
About Coldcard Mk3
The Coldcard Mk3 was a security-focused Bitcoin-only hardware wallet from Coinkite, popular among advanced Bitcoin users. It features a full numeric keypad, MicroSD card support for air-gapped PSBT transactions, two secure element chips, and a duress PIN feature. The Mk3 runs fully open-source firmware and is designed for maximum security with no altcoin support. It has been succeeded by the Mk4.