Bring analog endpoints into a modern SIP environment without overbuilding the solution. The HP Poly ATA 400 1FXS VoIP adapter is designed for organizations that need a compact, single-port bridge between legacy voice devices and Open SIP infrastructure. With one FXS port and an included power supply, this adapter is well suited to controlled deployments where a small number of analog phones, fax devices, or similar endpoints must remain in service. That makes it a practical choice for branch offices, reception areas, and targeted refresh projects where replacing every device is not the right economic move. For IT teams, the value is in precision: a defined port count, SIP compatibility, and a form factor that fits straightforward rollout plans. It helps extend the life of existing voice assets while keeping the communications stack aligned to current IP telephony standards. Compared with larger gateways, this model is easier to place, easier to manage, and better matched to single-endpoint conversion needs.