TL;DR
Both store your seed with stainless steel letter tiles and both survive a house fire. The Capsule is a small tube, the Billfodl a flat frame that’s easier to fill and read. Their shared weakness is that tiles can shift, so check them and consider a second, engraved plate.
| Cryptosteel Capsule | Billfodl | |
|---|---|---|
| Form | Small tube with tiles on a spine | Flat frame with numbered slots |
| Material | Stainless steel | Stainless steel |
| Filling it | Slide tiles onto the spine in order | Drop tiles into the slots per word |
| Reading it back | Unscrew and pull out the spine | Open the frame |
| Looks like | A small metal cylinder | A metal case |
What they have in common
Both use loose letter tiles: you store the first four letters of each word, which is enough because every BIP39 word is unique by its first four letters. Both are stainless steel and outlast paper by a long way.
The shared weakness
Loose tiles can move. If a holder is dropped, opened carelessly or damaged, tiles can fall out or slide, and you end up with the right words in the wrong order. That’s why each of my boxes also holds an engraved plate. See tiles, punched or engraved.
Which one
The Billfodl if you want something quick to fill and easy to check. The Capsule if you want the smallest, least noticeable object. Either way, check the plate against the device itself, as in step 5.
Cryptosteel Capsule: Buy from Cryptosteel · Buy on Amazon
Billfodl: Buy from Billfodl · Buy on Amazon