What are Hodlinox plates for?
Single plate with white case and interlocking plates with seal
Hodlinox plates are stainless steel plates designed specifically to store the seed phrase of your bitcoin wallet. A handheld electric engraving pen (see below) is used to engrave the seed phrase in the stainless steel plates.
Hodlinox plates are roughly the size of a small mobile phone.
What is the difference between the interlocking plates and a single plate?
Hodlinox interlocking plates
Both plates have the same function: to back up your seed phrase. Both plates are made of the same type of stainless steel. Which type of plate you choose is mostly a matter of personal preference but there are two reasons why interlocking plates are the slightly safer option:
- While a single plate can be ordered with a plastic case and plastic padlock seal to secure it, the interlocking plates consist of all metal parts, including the security seal.
- The interlocking plates can be disposed of separately once your wallet is empty. This makes it virtually impossible for anyone to restore the wallet and reconstruct your transaction history.
What is a seed phrase?
A seed phrase, also known as ‘mnemonic phrase’ or ‘recovery seed’, is a list of 12 to 24 words in which most of the information to recover a bitcoin wallet is stored. It is created when you first initialise your wallet and serves as a backup in case you need to restore your wallet, e.g. if you lose your hardware wallet. Each word in the seed phrase has 3 to 8 letters.
Example of a 12-word seed phrase:
Wallets that use a seed phrase are called HD wallets (Hierarchical Deterministic) and are based on a standard wordlist called BIP32. The BIP32 word list contains 2048 words in total.
Which wallets use a seed phrase?
Coldcard hardware wallet
Almost all modern wallets are HD wallets and thus use a seed phrase. Here’s a non-exhaustive list:
- Blue Wallet
- Green Wallet
Because the above wallets all use the same standard, you can always restore your wallet using any compatible program or hardware device, even if your seed phrase was generated somewhere else.
Why should I use Hodlinox plates?
When setting up your bitcoin wallet for the first time, you’ll probably write down your seed phrase on a piece of paper. But in case of a fire, flooding or other catastrophes, a piece of paper will be easily destroyed. Stainless steel however, will very likely survive any catastrophe as it’s water and fire resistant, and can endure extreme cold, physical force, electromagnetic pulses and various corrosive acids.
Why are Hodlinox plates better than other, similar products?
Hodlinox plates boast a unique combination of features that can’t be found in similar products:
- Simple locking mechanism
Hodlinox interlocking plates consists of two plates that are locked with a padlock seal. Locking or unlocking your seed phrase is very easy, while a tight closure is guaranteed when locked.
- Security seal
Both the single and interlocking Hodlinox plates can be sealed with a tamper-evident security seal that allows you to always verify that your seed phrase hasn’t been compromised. The interlocking plates even feature an all-metal seal.
- Immutable seed phrase
Because the words on the Hodlinox plates don’t consist of single letters or movable type but are engraved in the steel (using an easy to use pen-like engraver), it’s not possible to accidentally change or remove the seed phrase after it has been carved into the plates.
- Extra thick stainless steel
Hodlinox plates are made of 1.5mm (0.06 inch) stainless steel 316. This is much thicker than needs to be but ensures that your plates will withstand most impact and, in case of fire, resist heat more easily.
- Eight letters
You’re not limited to just 4 letters per word. Since the words in your seed phrase can be up to 8 letters long, there’s room for every letter of every word.
How do I write my seed phrase onto the Hodlinox plates?
Dremel 290 engraving pen
Engraving your seed phrase onto a Hodlinox plate is very easy when using a handheld engraving pen, such as the Dremel 290, which can be purchased online for about $25 (buy at Amazon or find with Google, find with DuckDuckGo).
Using an engraver is like writing with a large pen, it doesn’t require any special skills, practice or additional tools.
Alternatively you may also use letter stamps to stamp the words into the plates, just make sure that your hammer is sufficiently heavy and use a sturdy, flat surface. We recommend a letter height of 5mm or 0.2 inch.
Always engrave your seed phrase yourself, never have someone else to do this for you.
What is a passphrase?
A passphrase – also known as ’25th word’ – is a word or phrase that can be added to encrypt your seed phrase. Adding a passphrase creates a new wallet that is derived from the same seed phrase.
Some general guidelines for using a passphrase:
- Choose a phrase that is easy to remember but impossible to guess.
- Always save your seed phrase and passphrase in separate locations and never together. Do not engrave your passphrase on the same plate as your seed phrase.
- If you don’t trust yourself to remember the passphrase, we recommend storing it in your password manager.
What can I do to keep my bitcoin safe?
- Rule #1: never leave your bitcoin on an exchange but always transfer to a wallet of which you control the private keys.
- If you have an exchange account, always enable 2-factor authentication (2FA). Don’t use SMS-based 2FA.
- Use a hardware wallet such as Coldcard, Trezor or Ledger and secure it with a PIN code.
- Store the PIN code to your wallet in a password manager such as 1Password or Lastpass.
- Add a passphrase (also known as ‘25th word’ or ‘wallet extension’) to your seed phrase. Never store this passphrase with your seed phrase.
- Engrave your seed phrase on Hodlinox plates.
- Never share your seed phrase with anyone and don’t make digital copies (e.g. a photo).
- Do not trade but HODL.
Can I pay with creditcard, PayPal or another currency than bitcoin?
No, Hodlinox only accepts payments in bitcoin (BTC). It is possible to pay with Lightning.
My hardware wallet is stolen/missing
Assuming that you secured your hardware wallet with a PIN code and your PIN code is not compromised, your funds are probably still safe.
What to do: Use your seed phrase to restore your wallet on another wallet (any reputable HD wallet will do). Next, get yourself a new hardware wallet, configure it with a new seed phrase and transfer your funds to this new wallet.
Someone else may have had access to my seed phrase
Your seed phrase is more important than your wallet: immediate action is required!
What to do: Get a new wallet straight away (any reputable HD wallet will do), initialize it with a new seed phrase and immediately transfer your funds to the new wallet.
My computer might be infected with malware
The right course of action depends on the type of wallet you’re using:
Your computer can still be safely used for sending bitcoin but make sure to always verify the transaction details on the display of your wallet before confirming the transaction.
- Immediately disconnect your computer from the internet, switch it off and don’t use again until your funds are safe.
- Use your seed phrase to recover your wallet on a trusted device and transfer your funds to the new wallet as soon as possible.
- Get a hardware wallet, configure it with a new seed phrase and transfer your funds to the hardware wallet as soon as possible.
I forgot the PIN code to my hardware wallet
This is not a problem, just restore the wallet with your seed phrase, you don’t need the PIN code for this. You will be asked to choose a new PIN code (which is best stored in a password manager) during the recovery process.
I restored my wallet from the seed phrase but my funds don’t show up
This may have several causes:
- You may have forgotten to enter your passphrase (optional) before opening the wallet.
- You may have misspelled the passphrase. The passphrase is case-sensitive.
- You may have selected the wrong address type. There are 4 address types: Legacy, Pay to Script Hash, Native Segwit and Taproot.
- Your wallet may be using a different derivation path, see walletsrecovery.org for more information.