Every Raspberry Pi Zero build needs a MicroSD card to boot from, and this is the card we use and recommend. It’s sized correctly for the SeedSigner OS image with plenty of headroom, without paying for storage you’ll never use on a device that never touches the internet.
Class 10, UHS Speed Class U3, and Application Performance Class A1 ratings mean fast, reliable read/write performance both for flashing the OS image and for the device’s day-to-day operation. It ships factory-sealed for authenticity, with a full-size SD adapter included so you can use it in a laptop or card reader when flashing the image.


