What is Opendime? It is:

• Bitcoin on a stick.
• A Bitcoin piggybank.
• Not another hardware wallet since it has no PIN or password
• It's not like other "physical" bitcoin because nobody knows the private key until you physically alter the device.
• A disposable hardware wallet that can be used as cash.

Buy your Opendime

What’s new with V4?

It's an incremental (and not a radical) upgrade from v3. Coinkite has improved Opendime's:

• Form factor.
• Electrostatic discharge (ESD) protection
• Speed
• Recoverability in case of damage
• Blockchain viewing options (it added blockstream.info)

Why use it?

1. Gift: each Opendime costs about $17 and you can load it up with as much BTC as you want. Graduation present. Help someone buy a car or a house. Birthday gift for over $100.
2. You want to buy something expensive in a hurry.
3. Sell Opendimes with BTC. 
4. Anonymous transaction: it's almost impossible to know who spent the Opendime.
5. It’s better than a paper wallet because it has the upsides but also generates the private key safely.
6. Emergency money when you're traveling - it's like a traveler's check that works in the most repressive regimes. Wear it as a necklace under your shirt so that even if they steal your wallet and bags, you'll still have money. All you need a computer or a smartphone (with a USB-adapter).

What's cool about it?

• It acts like a read-only USB flash drive. Because it's read-only, there's no way to load malicious code on it.
• Works with any computer, laptop, or phone.
• A QR Image and Text files inside contain Bitcoin address and helpful information.
• Secure: the private key is generated inside the device, and is unknown until it's devirginized.
• Trustless: the private key is strictly in the device itself.
• it's safe to setup, verify and load an Opendime on an untrusted computer - impervious to malware and keyloggers as long as the private key has not been generated.
• Creates a QR code image for easy scanning.
• Off-chain: no miner fees, no confirmation delays.
• Uses Bitcoin message signing, normal (non HD) bitcoin payment addresses, and private keys in WIF format.
• It works with a phone or tablet.
• Lasts for 25-100 years.
• No password or seed phrase to deal with!
• Perfect for storing and anonymously transfering $100-$10,000 in BTC

See it in action

What should we expect in future versions? 

I bet that they will make a USB-C compatible version. 

It would also be great if they made one that is waterproof.

Buy your Opendime

More info

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