Abstract: An electronic device is provided that acts as cryptocurrency cash for point of sale or service transactional commerce. The electronic device is implemented using a microcontroller that can be manufactured inexpensively and physically handed over from one person to another just like cash. The device can hold cryptocurrency value without allowing the current holder to empty the assigned value of the device and hand the device over to an unsuspecting recipient of a transaction as untampered. This allows for digital cryptocurrency transactions that are instantaneous and which do not incur transaction costs. Cryptographically sound protocols are provided for the manufacturing and issuing of forms of the electronic device, verification of its untampered cryptographic keys and value and finally overtly removing the value to discard and/or reuse the electronic device. A method is provided which facilitates verification whether the electronic is genuine, untampered, and funded with cryptocurrency value.