Capsule A
Words 1–16
8 washers · front + back
Words 1–8 front · 9–16 back
Setup guide
How to use the custody kit
Engrave your 24-word seed onto washers, pack three capsules so any two recreate the wallet, then store them in different places. Work offline. Never photograph your seed.
Before you start
Generate your seed with a wallet you trust (ideally offline / air-gapped hardware). Have the full 24-word list written once on paper while you engrave — destroy the paper when the capsules are packed and checked. This guide is educational, not financial advice.
The 2-of-3 idea
You make three capsules. Each holds 8 washers (16 word sides). Together, any two capsules contain every word at least once.
Capsule B
Words 9–24
8 washers · front + back
Words 9–16 front · 17–24 back
Capsule C
Words 1–8 + 17–24
8 washers · front + back
Words 1–8 front · 17–24 back
Recovery combos
A + B → words 1–24
A + C → words 1–24
B + C → words 1–24
Single capsule loss
One capsule alone is incomplete. A thief or disaster that hits only one location cannot rebuild the wallet from that capsule alone.
Step by step
Follow the order below. Number washers lightly if it helps keep sequence clear.
Engrave with the tool
Use the engraver pen to mark each seed word on a washer face. Press firmly, keep letters readable, and double-check spelling against your BIP39 list. Work in a private space with no cameras.
First set of 8 washers — words 1–16
On the first 8 washers, engrave the
first 16 words: words 1–8
on the fronts and words 9–16 on the
backs (one word per side). These washers go into
Capsule A.
Second set of 8 washers — words 9–24
On the next 8 washers, engrave the
last 16 words of a 24-word seed (words
9–24): words
9–16 on the fronts and words
17–24 on the backs. These washers go
into Capsule B.
Third set of 8 washers — ends of the list
On the last 8 washers, engrave the
first 8 and last 8 words: words
1–8 on the fronts and words
17–24 on the backs. These washers go
into Capsule C.
Distribute the three capsules
Put each set of 8 washers into its orange capsule. Store the capsules so no two are in the same place.
Recommended placement:
1) Your safe or primary secure spot · 2) A trusted friend or family member locally · 3) As far away as practical (another city/region, trusted person, or secure storage you can still access if needed).
Tips that matter
Small habits that keep the scheme strong.
Holders of capsules do not need to know each other. That reduces social graph risk if one relationship changes.
They should be reachable if you ever need the seed — death, travel, fire, or device failure is when two capsules must come together quickly.
Tell stewards only what they need: “This is a sealed capsule; return it to me or my estate if asked.” You do not need to explain Bitcoin.
After packing, dry-run recovery with the word lists only (not on a hot phone if avoidable): pick any two capsules’ word sets and confirm you can order words 1–24 correctly.
Never store a full digital photo of all washers. Never engrave your passphrase (25th word) on the same washers unless you fully accept that risk.
Label capsules A/B/C on the outside if you want — but don’t write the full seed mapping on a sticky note left with the capsule.
Important limitations
This is practice-grade metal
Washers and hand engraving are a huge step up from paper, and a free, practical alternative to premium plates. Extreme fire or corrosion scenarios may still differ from industrial solutions.
You are responsible for keys
If you lose two capsules, the wallet may be unrecoverable. If someone obtains two capsules, they may recover it. Distribution is the security model.
Need the hardware?
Request your free kit, then follow this guide offline.