Cryptnox crypto hardware wallet dual card set for secure cryptocurrency cold storage

Cryptnox crypto card with FIDO2 authentication

Cryptnox secure crypto hardware wallet card

Cryptnox hardware wallet NFC smart card dual set

Cryptnox NFC hardware wallet secure chip technology

Cryptnox SA

Cryptnox Crypto Hardware Wallet — Smart Card Cold Storage with Dual-Card Backup

The Cryptnox crypto hardware wallet is a Swiss-engineered smart card that secures Bitcoin, Ethereum, 1,000+ EVM tokens, Tron (TRX, TRC-20), XRP, and other supported chains entirely on-card via an EAL6+ certified secure element. The Dual Card Set ships uninitialized — you set up both cards yourself via a brief paired ceremony in the Cryptnox app, with the seed generated jointly inside both cards’ certified TRNGs and committed to both cards at once (no 24-word phrase to write down). Two more options: inject an existing 12/24-word BIP39 seed for migration or off-card backup, or initialize a single card from its on-chip TRNG for short-term use. Randomness comes from the chip’s EAL6+-certified on-chip TRNG — every possible seed is equally likely, and impossible to predict in advance. See the full default list of supported coins and blockchains — more chains and coins can be added manually.

Cards also ship with FIDO2 Functionalities now!

For more information, Learn about Cryptnox FIDO2 security key.

CHF 37.25

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Description

Customer rating: ★★★★½ 4.4 / 5 — based on 45 Amazon customer reviews. Read on Amazon.

The Cryptnox crypto hardware wallet is a Swiss-engineered smart card that secures your Bitcoin, Ethereum, 1,000+ EVM-compatible tokens, Tron (TRX and TRC-20), XRP, and other supported chains entirely on-card. Private keys are generated inside an EAL6+ certified secure element and never leave the chip. The Dual Card Set ships uninitialized — for a critical security reason: nobody between the chip foundry and your hands ever sees your seed. You initialize the cards yourself in the Cryptnox app, using one of three methods (see below).

Cold storage in a smart card form factor

Most hardware wallets are USB devices that plug into a networked laptop. The Cryptnox crypto hardware wallet is a smart card — between transaction signings the card is fully offline, with no charging, no batteries, and no cables. To sign a transaction, you bring the card near your phone in the Cryptnox app (the NFC antenna location varies by phone model). The brief signing session uses an authenticated, encrypted secure-messaging channel between the card and the app — the link itself cannot be eavesdropped or replayed, even though it travels over NFC. Outside that signing handshake, the card stays fully offline — colder than any USB hardware wallet that remains plugged into a networked machine.

Three ways to initialize — choose what fits your security posture

Every initialization path uses the card’s on-chip TRNG (true random number generator) — part of the chip’s Common Criteria EAL6+ certification. Every possible seed is equally likely, and impossible to predict in advance, not even by Cryptnox.

Method 1 — Paired dual-card ceremony (recommended for the Dual Card Set): with both cards present, the Cryptnox app guides you through a brief interactive mini-ceremony. The seed is generated jointly inside the two cards’ certified TRNGs and committed to both cards at the same time. The seed never exists outside the two secure elements. Result: identical seed on both cards — the first card is for daily use, the second is your built-in backup, stored somewhere safe. If the main card is ever lost or damaged, the backup restores full access instantly, with no 24-word seed phrase to write down. Step-by-step: Dual Card setup tutorial.
Method 2 — External seed injection (migration or off-card backup copy): the cards can accept an externally generated 12/24-word BIP39 seed via the Cryptnox app. Use this if you’re migrating from another wallet (Ledger, Trezor, MetaMask, etc.) and want to keep the same seed, or if you want to keep a copy of the seed off-card under your own protection. Both cards in the Dual Card Set can be loaded with the same injected seed. See our 12/24-word mnemonic setup tutorial.
Method 3 — Single-card random init (short-term / specific use): a single card initializes itself with a random seed pulled from its on-chip certified TRNG. There is no backup — if the card is lost, the funds are unrecoverable. Only suitable for small short-term holdings or specific experimental use cases. Most users should pick Method 1 or 2.

MetaMask, Uniswap, and DeFi compatibility

The Cryptnox crypto hardware wallet works with two standard integrations:

MetaMask browser extension — pair Cryptnox via the QR-based wallet-signing standard. MetaMask handles dApp connection and transaction building in the browser; the Cryptnox card signs each transaction on-device after a phone confirmation. Step-by-step: MetaMask + Cryptnox setup guide.
DeFi platforms (Uniswap, Aave, bridge aggregators, NFT marketplaces, etc.) — connect via WalletConnect. The dApp displays a QR code, you scan it in the Cryptnox app, and sign with the card. See how to use WalletConnect with Cryptnox.

In both paths, your private keys never leave the card’s secure element. See the full list of supported coins and blockchains for the complete catalog of EVM chains, altcoins, and tokens.

How to use the card on your phone or desktop

For mobile signing, just hold the card near any NFC-capable phone in the Cryptnox app — no contact reader required. For desktop browsers, scan a WalletConnect QR code with the Cryptnox app and sign on your phone. If you prefer to sign from a desktop directly via the contact interface, the Cryptnox dual-slot Smartcard Reader works with the card via the ISO 7816 contact interface.

For setup walkthroughs, integration guides, and troubleshooting, browse our hardware wallet tutorials hub.

Features

Cold storage in a wallet-friendly card

True cold storage: the card is offline 100% of the time except during the brief signing session. No always-on USB connection to a networked laptop.
EAL6+ secure element: the same chip class used in banking and government-grade smart cards. Private keys are generated and stored inside the chip; they never leave it.
Certified on-chip TRNG: seeds are produced by an on-chip true random number generator that is part of the chip’s Common Criteria EAL6+ certification — every possible seed is equally likely, and impossible to predict in advance, even by Cryptnox.
Encrypted signing channel: every signing session between the card and the Cryptnox app uses an authenticated, encrypted secure-messaging channel — the data exchanged with the card cannot be intercepted or replayed, even on the NFC link.
Wallet-friendly form factor: credit-card sized, fits in any wallet cardholder. No keychain dongle, no charging cable, no battery.
Ships uninitialized: the cards arrive blank — you set them up yourself in the Cryptnox app, so nobody upstream ever sees your seed.

Three ways to initialize — choose your seed-management model

Paired dual-card ceremony (default for the Dual Card Set): both cards run a brief interactive ceremony in the Cryptnox app and commit the same seed at the same time. The seed is generated jointly by the two cards’ certified TRNGs and never leaves either secure element. Highest-assurance posture, with built-in backup. See the Dual Card setup tutorial.
External seed injection: inject a 12/24-word BIP39 seed via the Cryptnox app. Use this for wallet migration (importing from another wallet) or when you want a copy of the seed off-card under your own protection. Walkthrough: mnemonic setup tutorial.
Single-card random init: a single card initializes itself from its own certified TRNG. No backup — only suitable for short-term holdings or specific experimental use cases (if the card is lost, funds are unrecoverable).

Supported coins and blockchains

The Cryptnox crypto hardware wallet supports Bitcoin, Ethereum, 1,000+ EVM-compatible tokens and altcoins, Tron (TRX and TRC-20 tokens), and XRP (XRP Ledger) — all pre-programmed in the free Cryptnox app for iOS and Android. The complete default list of coins and blockchains is published at cryptnox.com/coin-blockchain-support; advanced users can also add additional chains and tokens manually. WalletConnect adds compatibility with the entire DeFi ecosystem on every supported chain.

How signing works

Mobile: install the free Cryptnox app on iOS or Android, build the transaction in the app, hold the card near the phone (NFC antenna location varies by phone) to sign. Signing channel is encrypted end-to-end.
MetaMask + browser: pair the card via the QR-based wallet-signing standard. Setup walkthrough.
DeFi (Uniswap, Aave, NFT marketplaces, bridge aggregators): via WalletConnect. The dApp displays a QR code; scan it in the Cryptnox app and sign with the card.
Desktop direct (optional): use a contact smart card reader like the Cryptnox dual-slot Smartcard Reader to sign without a phone.

What’s in the Dual Card Set

2 × Cryptnox crypto hardware wallet cards (primary + backup), shipped uninitialized for security
Both cards from the same production batch — uniform firmware
Initialize together via the paired-card ceremony (default), or use external seed injection / single-card init if your scenario demands
Free Cryptnox app for iOS and Android

Browse the full hardware wallet tutorials catalog for setup walkthroughs, integration guides, and troubleshooting.

Specifications

Technical specifications

Form factor: ISO/IEC 7810 ID-1 (CR80, credit-card size)
Interface: NFC (ISO/IEC 14443 Type A) + contact (ISO 7816)
Secure element: EAL6+ certified chip
Random number generator: EAL6+-certified on-chip TRNG (true random number generator) — every possible seed is equally likely, impossible to predict in advance, even by Cryptnox
Key storage: private keys generated and stored inside the secure element; never leave the chip
Communication security: authenticated, encrypted secure-messaging channel between the card and the Cryptnox app — protects every signing session against eavesdropping or replay
Initialization: cards ship uninitialized; the user initializes them in the Cryptnox app via one of three methods — (1) paired dual-card ceremony with simultaneous on-chip seed generation in both cards, (2) external 12/24-word BIP39 seed injection (for migration from another wallet or off-card backup), or (3) single-card random init from the on-chip TRNG (no backup; short-term / specific use only)
Power: passive — no battery, energy harvested from the NFC reader’s RF field
Mobile app: free Cryptnox app for iOS and Android
Desktop integrations: MetaMask via QR-based wallet-signing standard; WalletConnect for DeFi platforms; optional direct desktop signing via the Cryptnox dual-slot Smartcard Reader over ISO 7816 contact

Pack contents

2 × Cryptnox crypto hardware wallet cards (primary + backup), shipped uninitialized
You initialize both cards together in the Cryptnox app via the paired-card ceremony, or independently via external seed injection or single-card init

Compliance

EAL6+ secure-element certification
ISO/IEC 7810 (card form factor)
ISO/IEC 7816 (contact interface)
ISO/IEC 14443 (NFC interface)

Frequently Asked Questions

Which cryptocurrencies does the Cryptnox hardware wallet support?

The Cryptnox hardware wallet card supports a wide range of cryptocurrencies through the free Cryptnox app — Bitcoin, Ethereum and the 1,000+ EVM-compatible tokens and altcoins, Tron (TRX and TRC-20 tokens), and XRP (XRP Ledger). The full list of coins and blockchains pre-programmed in the app is published at cryptnox.com/coin-blockchain-support — additional chains and tokens can be added manually for advanced users. Through WalletConnect, you can also use the card with DeFi aggregators, DEXs, NFT marketplaces, and bridge aggregators on any chain your dApp of choice supports.

Is this a cold storage wallet?

Yes — it’s a true cold-storage device. Private keys are generated inside the card’s EAL6+ secure element and never leave it. The card only signs transactions when tapped against your phone via NFC; between taps, nothing is online. That’s colder than any USB hardware wallet that plugs into a networked laptop.

Do the cards ship pre-initialized? How do I set them up?

No — the cards always ship blank, for a critical security reason: nobody between the chip foundry and your hands ever sees your seed. You initialize the cards yourself in the Cryptnox app, using one of three methods:

Paired dual-card ceremony (recommended for the Dual Card Set): with both cards present, the Cryptnox app guides you through a brief interactive mini-ceremony. The seed is generated jointly inside the two cards’ certified TRNGs and committed to both at the same time — it never exists outside the two secure elements. You get a primary card plus a built-in backup, with no 24-word seed phrase to write down.
External seed injection: inject an existing 12/24-word BIP39 seed via the Cryptnox app — useful if you’re migrating from another wallet (Ledger, Trezor, MetaMask, etc.) and want to keep the same seed, or if you want to keep a copy of the seed off-card under your own protection. Both Dual Card Set cards can be loaded with the same injected seed.
Single-card random init: a single card initializes itself with a random seed pulled from its on-chip certified TRNG. There is no backup — only suitable for short-term holdings or specific experimental use cases.

In every case, the seed is produced by an on-chip TRNG (true random number generator) that is part of the chip’s Common Criteria EAL6+ certification — every possible seed is equally likely, and impossible to predict in advance, even by Cryptnox.

How is the Cryptnox “dual card” different from a single hardware wallet?

The Dual Card Set arrives uninitialized — both cards are blank when you receive them. Once you have the cards in hand, the Cryptnox app guides you through a brief paired-card ceremony where both cards generate the same seed simultaneously inside their certified on-chip TRNGs. The seed is committed to both cards at once and never exists outside the two secure elements. The first card is your daily-use card; the second is your built-in backup, stored somewhere safe. If the main card is ever lost or damaged, the backup restores full access instantly — no 24-word seed phrase to write down or protect. Alternatively, both cards can be loaded with a 12/24-word BIP39 seed injected via the Cryptnox app, if you’re migrating from another wallet or want to keep a copy of the seed off-card.

Does the Cryptnox wallet work with MetaMask, Uniswap, and other dApps?

Yes — through two standard integrations depending on the platform:

MetaMask browser extension: pair Cryptnox via the QR-based wallet-signing standard. MetaMask handles dApp connection and transaction building in the browser; the Cryptnox card signs each transaction on-device after a phone tap. You keep MetaMask’s familiar dApp UX with hardware-wallet-level security underneath.
DeFi platforms (Uniswap, Aave, bridge aggregators, NFT marketplaces, etc.): connect via WalletConnect. The dApp displays a QR code, you scan it in the Cryptnox app, and sign the transaction by tapping your card against your phone.

In both paths, your private keys never leave the card’s secure element.

How do I actually sign a transaction — app, cable, or what?

You install the free Cryptnox app on iOS or Android, connect your hardware wallet card by tapping it against your phone (NFC), and confirm transactions in the app. For desktop browsers, scan a WalletConnect QR code with the app and sign on your phone. No USB cables, no batteries, no charging.