CryptoSteel Capsule review

by Colin Aulds
Updated 11/26/2019


  • Tray is easy to get tiles from
  • Lifetime satisfaction guarantee w/ refund (though Cryptosteel is notorious for poor customer service)


  • Closed source (patent pending)
  • Tiles could fall out, losing your backup
  • Tray could be easily spilled

Who Should Buy a Seed Backup Device

Crypto investors with any significant sum of bitcoin

Crypto investors who want cold storage and wallet restoration

Crypto investors who want control over their own finances

Why Buy a Seed Backup?

With bitcoin’s solution to the double-spend problem, digital scarcity was introduced to the world. The ability to create a unique, unreplicable digital asset was a first of its kind.

The need to manage and safely back up such sensitive items was eventually found in the BIP 39 method.

These 12- or 24-word combinations are the sole source for restoring a bitcoin wallet and thus warrant significant protection.

But storing these digitally proved again and again far too dangerous.

Protecting your seed words is mandatory for anyone planning to hold a significant sum of bitcoin for any duration of time longer than a few days. 

Ensuring that your wallet can be restored following a catastrophe such as a home fire, earthquake, or even a nuclear detonation provides a high degree of comfort for the serious HODLer.

Eventually, companies sprang up in order to address this need and produced the various real-world seed phrase backup devices we use today.

These devices were developed as a way to increase the longevity and security of the seed phrase far above and beyond what a paper wallet is capable of.

There have been many iterations on this approach as the best way to both record and store the seed phrase in a secure and incorruptible way was tested and incrementally improved.

Among these is the popular slot-and-tile, cassette-secured method using individually etched or stamped characters, an open source design used by Cryptosteel and others.

More recently, a new iteration on the previous cassette-based model was introduced with the Cryptosteel Capsule.
Protecting your seed words is mandatory for anyone planning to hold a significant sum of bitcoin for any duration of time longer than a few days.

Ensuring that your wallet can be restored following a catastrophe such as a home fire, earthquake, or even a nuclear detonation provides a high degree of comfort for the serious HODLer.

Cryptosteel Basics

Designed and manufactured in the UK, Cryptosteel builds on its first product: an open source implementation of the cassette and tile version of the steel backup device.

The Capsule breaks this legacy with its predecessor by introducing a new design — one which is patent pending.

Being that the Capsule’s design is closed to competition or improvement, Cryptosteel has done an abrupt about-face and betrayed their original ethos which aligned closely with bitcoin’s.

The Capsule can allow for the storage of 123 total tiles (not only letters and numbers but also special characters).

TwoHierarchical Deterministic 12-word seed phrases or one 24-word (96 characters needed) will fit within the capsule as well as other data such as a private key.


The Cryptosteel retails for ~$100 USD after shipping.

Unboxing & Impressions

The Cryptosteel Capsule ordered for this review was shipped internationally to the United States via DHL in a plain brown package. The product packaging itself is slick and heavily branded.

Contained within the box is a pair of molded plastic trays which house the tiles and Capsule. 

The outer box unfolds to an inner diagram which assists assembly and identifying the locations of each letter or number. 

A small piece of uncredited “thank you” artwork embossed on cardstock is included in the packaging, likely the work of Rafael Akahira.

The artwork prominently touts the words “open source” and obviously relates not to the Capsule, but rather to their previous cassette-based product. 

The artwork doesn’t conform with the branding of the product and is generally unappealing. 

Due to the poor fit with factual information, the half-hearted support (there is no outbound link to the artist on the website) and jarring aesthetics, the art would be better left out of the packaging of the Cryptosteel Capsule in my opinion. 

The online marketing is unusual for such a device as well, being that one of the main images show it slung around the neck of a shirtless male model (surprisingly not nestled within the cleavage of a well-endowed female model).

This seems to purely be some kind of sex appeal or of suggesting potential buyers (the vast majority being men) to fancy themselves as alpha warrior types for choosing the product. 

Capsule Description

The Cryptosteel Capsule is a stainless steel cylinder with rounded corners and a lightly knurled exterior surface. It measures 102mm (4”) long with a 16mm (.63”) diameter. The walls of the capsule are about 1.5mm (1/16”) thick.
All parts of the Cryptosteel are solid stainless steel. 

A small rectangular core (on which the character tiles are placed) protrudes from the cap and is secured to the longer section with a threaded cap.

This cap features a small perpendicular hole for connecting the device to a metal slat. 
The threads are somewhat fine but still allow a bit of slack which could cause problems opening or closing it in the long run. 
The tiles have a convex obverse, a concave reverse and lowercase characters are framed by two dots for easier reading. 


The Cryptosteel replicates the offline storage of private keys, passwords, and wallet recovery seeds without the need for any third-party involvement. 

It is the latest (though not the best) iteration on the variety of products which have made disaster-proofing of alphanumeric information available to bitcoiners or other security-conscious people.

Storable Information Formats

  • BIP39 (unabbreviated 12-word recovery seeds) 
  • BIP39 (4-letter abbreviations of 24-word recovery seeds) 
  • Shamir Backup SLIP0039 (4-letter abbreviations of 20-word recovery seeds) 
  • BIP32 root keysWIF private keys 
  • Monero mnemonic seeds (25-word recovery seeds) 
  • Random ASCII passwords 
  • PINs 
  • Insurance account numbers 
  • Master passwords to your password manager
  • Bank account info and passwords 
  • GPS coordinates 
  • Rainbow Codes 
  • Elliptic curve coordinates 

Device Setup

The capsule can be set up directly out of the box by simply unscrewing the cap and adding tiles.

A small fabric ribbon in the slot at the end of the core reminds you to add a fastener once your tiles have been put in place. 

Once your data has been added the cap is replaced.

Optional additional steps are adding a tamper-evident seal or possibly obscuring the device in some other item or location; a good practice for any physical backup device. 

While loading the tiles is marginally faster, recovering from this device takes a great deal longer than it would from a cassette style backup, so if you ever need to recover quickly, this is not the backup for you.
Unfortunately, there is a fatal flaw which awaits if you incorrectly secure the fastener tile. If not completely closed around the end of the core, the tiles can fall off when it is opened to restore a wallet.

In this case you would experience a total loss of your coins — an outcome that recovery seed backups are specifically designed to prevent. 

This tile was incorrectly fastened at the end of the process unwittingly by the reviewer and had to be bent further to actually secure it.

The tiles would have fallen off had the cap been being held upside down, only luck saved the backup in this instance. 


The Cryptosteel Capsule is a poor addition to the variety of options for backing up your seed recovery words.

Due to the potential of catastrophic data loss if the fastener tile is incorrectly placed, we cannot endorse this product and advise that you look for alternatives that keep this threat in mind. 

The bizarre ‘open-source’ artwork on a patent pending product, complicated device setup, and lack of any real additional security provided by the tile arrangement makes one wonder why they would buy the capsule at all. 

Given that the capsule is priced even higher than cassette model, this further has us wondering what the point of this product was besides a cash grab. 


1.5 / 5