If you use Monero, your seed phrase is everything. In this review I show how to use the XMR Street 316L Seed Capsule set to permanently back up a 25‑word Monero seed phrase in stainless steel, offline and under your sole control. Paper burns and USB drives fail; this kit gives you a fire‑resistant, rust‑resistant, electronics‑free backup.
Links
- Order from XMR Street: https://xmrstreet.store/
- Find on Monerica (Businesses → Monero Hardware): https://monerica.com
Disclosure: Not sponsored and not an affiliate link. Educational only—this is not financial, tax, or legal advice. Always consult a professional for your situation.
What’s in the Kit
- 316L steel seed capsule (compact and heavy‑duty).
- 16 double‑sided 316L steel washers (each holds two words).
- Steel stamping base (heavy duty) and a hard plastic alignment guide.
- Full set of letter/number/symbol stamps (upper/lowercase and punctuation).
- Monero stickers and packaging materials.
Note: The full kit is substantial and the finished capsule is quite solid. Consider buying more than one capsule if you want multiple geographically separated backups.
Before You Start
- Verify your seed in a Monero wallet first—confirm it restores correctly and note the receive address you’ll use afterward.
- Prepare a quiet, private workspace (garage/basement/workshop). Stamping is very loud metal‑on‑metal and not apartment‑friendly.
- Have a hammer and stable surface ready.
- Remember: stamps are mirrored. Double‑check orientation before each strike.
How the Washers Are Used
Monero seed phrases are 25 words. Each washer is double‑sided, so you stamp word number + word on the same side:
- Washer 1: front =
01+ word 1, back =02+ word 2 - Washer 2: front =
03+ word 3, back =04+ word 4 - …continue up through word 25 (you will use 13 washers total; one side will be unused).
Step‑by‑Step Stamping
- Insert a washer into the steel base.
- Place the plastic alignment guide on top.
- Pick the required character stamp and seat it in the guide hole.
- Hold like a nail; strike the top firmly 2–3 times with the hammer.
- Double‑check orientation each time—stamps look backwards.
- For long words, rotate the washer slightly between letters and alternate between adjacent guide holes to pack characters tightly and keep them aligned.
- Repeat for all 25 words. I stamped every letter (not just the first 4) for clarity and redundancy.
Time & Noise
Expect a significant time commitment—roughly 2–3 hours to stamp all 25 words carefully. It is very loud; plan accordingly and do not attract attention.
Tips for Neat, Error‑Free Results
- Keep stamps organized alphabetically and return each after use.
- Check mirror orientation before every strike; mistakes are permanent.
- Hold stamps steady and vertical to avoid slanting.