Keystone 3 Pro

The Keystone 3 Pro is a 4-inch touchscreen hardware wallet with three separate secure element chips, a fingerprint reader, and firmware that is open source right down to the secure element implementation.

Three secure elements, each with one job

• Microchip ATECC608B — secures your recovery phrase
• Maxim DS28S60 — creates a trusted environment for recovery storage
• Maxim MAX32520 — secures your fingerprint data

Splitting these roles across separate chips means compromising one does not hand over the wallet.

Open source, including the parts nobody else opens

Keystone publishes not only firmware but secure element firmware, circuit layouts and the bill of materials. Almost every competitor keeps its secure element implementation closed, because chip vendors require it. Keystone describes the device as 100% open source.

Signing: QR by default, USB available

The Keystone 3 Pro signs by scanning QR codes with its camera, so it can operate with no connection at all. It has no Bluetooth and no WiFi.

To be accurate: the USB-C port does carry data, used for firmware updates and MetaMask integration. Keystone lets you switch it to charge-only mode if you want a strict air gap. Many retailers describe this wallet as "QR only" — that is not what Keystone's own documentation says, and you should know exactly what you are getting.

Specifications

• 4-inch LCD touchscreen, 480 x 800
• Fingerprint sensor — up to 3 fingerprints, for unlocking or for signing
• USB-C (data, switchable to charge-only), camera, MicroSD slot (card not included)
• 62.44 x 103.9 x 12.08 mm, 103 g, PC + ABS
• 1000 mAh lithium-ion battery
• PCI-level anti-tamper protection

Backup and wallets

• 12 or 24-word recovery phrase, or Shamir Backup with a configurable number of shares
• Manages 3 separate wallets at once, each with its own PIN
• Passphrase supported

Bitcoin-only firmware

Keystone offer a Bitcoin-only firmware that strips out all altcoin code to narrow the attack surface. It is a firmware you flash, not a separate device, so you can decide after buying.

Coins and compatibility

• 5,500+ coins and tokens across 200+ blockchains, and 45+ software wallets
• Keystone Nexus app on iOS and Android, connected by QR scan
• MetaMask and OKX Web3 Wallet integrations

Common questions

Is it fully air-gapped?
It can be. QR signing needs no connection, and USB data can be switched off. Out of the box the USB port carries data for firmware updates.

Why three secure elements?
Each protects a different thing, so a weakness in one does not expose your recovery phrase, your storage environment and your fingerprint all at once.

Can I really run three wallets?
Yes, three separate seed phrases on one device, each behind its own PIN.

Does it work with an iPhone?
Yes, through the Keystone Nexus app by QR scan.

Is a MicroSD card included?
No. The slot is there for firmware updates and backups, but you supply the card.

Buying from SIAMBC

SIAMBC is Thailand's authorized Keystone distributor, with a physical store in Bangkok. Every unit is new, sealed and sourced directly. Support is available in Thai and English.

ONE RULE TO REMEMBER

Anyone who asks for your recovery phrase is a scammer. No exceptions.

Neither SIAMBC nor Keystone will ever ask for it, whatever reason is given — warranty claims, identity verification, system updates or account recovery. Those words are the key to your funds. Whoever has them owns your crypto, and it can never be recovered.