A Coldcard Mk.3 (buy here)
A USB-A to micro USB cable
A microSD card (32GB or less)
An adapter to connect the USB-A cable and/or the microSD card to your computer
A desktop or laptop computer with one of the following operating systems:
MacOS
Windows
Debian / Ubuntu
Linux
Paper and pen for the wallet backup process
60 minutes of your time
An internet connection