Keystone Pro 3 QR-based airgap hardware wallet by Keystone (formerly Cobo Vault). Hardware - 4-inch color touchscreen. - Battery-powered. - Removable secure element module. - Fingerprint sensor. - Camera for QR scanning. - microSD slot. Connectivity - No USB / Bluetooth for signing. QR + microSD only. - USB only for charging + firmware updates. Currencies Multi-coin: Bitcoin, Ethereum, Cosmos, Solana, etc. Bitcoin-focused features: - BIP39 seed. - BIP44/49/84/86. - Multisig support. - PSBT signing. Backup - 24-word seed. - Encrypted microSD backup. - Optional Shamir Backup (SLIP-39). Compatib…