This article provides an in-depth technical description of how to decode the QR codes which the Cobo Vault hardware wallet uses to communicate with an internet-connected device. The QR code feature was important for gaining the trust of consumers, as it transparently enables anyone with the necessary technical skills to read every bit of information that enters or leaves the hardware wallet. Recognized as an important contribution by experts in the Bitcoin community, this article formerly ranked second on Google for “QR code hardware wallet”, an important selling point for the product. I provided creative direction for the image that was put together by our graphic designer.