Features: 2 ports (Expandable to 6), Provides 4 hours of voice message storage (expandable to 8 hours), Supports up to 64 Mailboxes, Flash based memory, Enhanced Personal Custom Service offers more options based on Day, Date and Time. Windows Based Programming, Built in USB Port for On site Programming of your KX-TVA50, Improved Sound Quality, Automated Attendant Service, Live Call Screening, Multi-lingual Voice Prompts, In band Integration, Remote and On Site Administration (Remote Modem KX-TVA296), Caller ID Name Announce and Call Routing, Personal Greeting or Caller ID, Quick Setup for KX-TA, KX-TD and KX-TDA systems.