PTI-401 is a unique modem that relies on software without the need for a modem processor. With main features such as compact size, higher functionality and easy upgradability, the PTI-401 also comes featured packed with ITU-T V.92, ITU-T V.90 and K56 Flex auto-negotiation with auto-fallback to ITU-T V.34 and below. Software upgrades are made simple with a user-friendly "Upgrade Utility", making PTI-401 easy for end-users to keep update with new communication technology.