Still on the same mission: make this wallet last. Two more parts got upgraded for the first build — the brain went industrial-grade, and the display connector is gold.
A hardware wallet is stored far more than it is operated. It sits in a drawer through summer, in a safe through winter, sometimes in a car or a bank vault, and it has to still enumerate and sign correctly the day you finally need it.
An industrial-grade brain
For the first build we're moving the microcontroller to the industrial temperature grade: the STM32F205RET7, rated from -40 °C to +105 °C — up from the +85 °C part we started with. A wallet might sit in a hot car, a safe, or a drawer in a tropical country; industrial-grade silicon keeps working where consumer parts start to drift. And it's still the same open, general-purpose STM32 — no secret chip, just the tougher temperature bin.
Gold where it counts
The screen connects through a thin flex cable, and its connector is exactly the kind of small part that quietly corrodes over the years. We chose a Hirose FH34 connector with gold-plated contacts. Gold doesn't oxidise, so the connection stays clean and reliable for the whole life of the device — not just the first year.
Small parts, long life
Nobody puts the temperature grade of a microcontroller or the plating on a connector on a product page. But those unglamorous choices are exactly what decides whether a device still works in fifteen years. We'd rather spend our attention there than on another feature nobody asked for.
Why industrial grade for a device that lives on a desk
The −40 to +105 °C rating is not there because anyone will use the device at those temperatures. It is there because the part is specified to keep working across a range that ordinary storage will never approach, which is a different and more useful promise than surviving a comfortable office. The same logic drives the gold-plated display contacts: gold does not oxidise, and a connector that sits untouched for five years in a humid drawer is exactly where a cheaper plating starts to fail. Choosing for storage rather than for use is most of what separates a hardware wallet built for a decade from one built for a review cycle.
More from the bench soon. If you want to see the industrial build in person, we'll have the prototype at Bitcoin Thailand Conference 2026.