Ledger Nano Bitcoin Wallet is a hardware wallet with a form factor like a USB-memory. Since the Bitcoins are stored offline and in the hardware it is very secure.
It is avaible in three different sizes:
- Ledger Nano S
- Ledger Nano
- Ledger HW.1
The Nano S is the new wallet and has a physical button where you need to push to acknowledge the transaction.
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