Prokey Optimum is a web-based hardware wallet that allow you manage 1500+ cryptocurrencies through a browser only, without install any application and bridges. on the other hand, it's protected from supply-chain attack because of using mutual authentication. in other words, If a device is tampered physically, it cannot be used to gain access to the wallet due to an authentication needed from the servers. Prokey Optimum hardware wallet features * Secure Firmware with mutual authentication * supports Bitcoin, Ethereum, Litecoin, Bitcoin-cash, USDT and 1200+ cryptocurrency * Manage through a web browser only * Manage all digital assets in one single platform * Easy to use for newbie and non-technical users * Support USDT on both Omni and Ethereum blockchain (ERC20)