What Is SATSCARD?

SATSCARD is a physical bearer Bitcoin card with ten independent key slots. Bitcoin sent to the current sealed slot can travel with the card: a recipient can verify the card and its funding, keep it sealed, pass it again, or unseal the slot and sweep the funds into a wallet.

What “bearer Bitcoin” means here

A SATSCARD handoff changes who possesses the device and its six-digit card verification code (CVC). It does not, by itself, move bitcoin on-chain. The bitcoin remains at the current slot address until someone unseals that slot and creates a normal Bitcoin transaction to sweep the funds elsewhere.

That makes the card useful when a physical object is part of the experience: a birthday gift, a first-bitcoin lesson, an artist edition, or an in-person exchange. The recipient should still verify the card and current slot before treating the handoff as final.

The four-part lifecycle

1. Verify. Use a compatible wallet or the card's signed NFC verification link to inspect the card. A wallet integrating the open protocol can perform deeper checks, including the factory certificate.
2. Fund. Send bitcoin to the address for the current sealed slot and wait for the confirmation policy appropriate to the amount and situation.
3. Hand over. Transfer the card, CVC, and RF-blocking sleeve. No new on-chain transaction is required for the physical handoff.
4. Unseal and sweep. When the holder wants normal wallet custody, a compatible app unseals the current slot, obtains its key material, and sweeps all funds to a new wallet address.

Unsealing cannot be undone. The card advances to its next independent slot, and the old slot should not receive new funds.

What the ten slots do

SATSCARD protocol slots are numbered 0 through 9 internally; this site describes them as slots 1 through 10 for people using the card. Each slot has a separate key rather than being a child of one shared seed. The factory initializes the first slot. When a later slot is initialized, compatible software can contribute a 32-byte chain code that is combined with secret card-generated entropy.

The printed QR code on the card is for the factory-initialized first slot. After that slot is unsealed, use a compatible app or fresh tap workflow to obtain and verify the current address. Learn more in How SATSCARD slots work.

What possession does—and does not—prove

Possession gives a person access to the physical card and printed CVC. It does not automatically prove that:

• the card is genuine;
• the current slot is still sealed;
• the displayed address is the current slot address;
• the funding transaction is confirmed and unspent;
• no one else recorded exposed key material after unsealing.

A recipient should follow the verification and acceptance checklist. The amount, transaction history, and required confirmations remain Bitcoin network questions, not facts the NFC chip can guarantee.

SATSCARD compared with a normal wallet

Question	SATSCARD	Normal Bitcoin wallet
Normal transfer model	Hand over a funded sealed card	Sign and broadcast an on-chain transaction
Recovery model	Unseal one slot and sweep its key	Restore from the wallet's documented backup
Reuse	Ten independent slot lifecycles	Repeated address derivation and transactions
Best fit	Gifts and physical handoffs	Ongoing spending, saving, and transaction management
Display	None	Depends on the wallet/device

When to choose something else

Use a regular wallet when the recipient is ready to receive on-chain directly. Use a display-equipped hardware wallet such as COLDCARD for large or long-term savings where independent transaction review matters. Use TAPSIGNER when one owner wants a reusable NFC signing key rather than something intended to be passed to a new owner.

Ready to use the card? Read how to gift bitcoin or how to unseal and sweep.