The small sized 56K USB Fax Modem is to connect phone to PC via USB port to make / receive voice calls and send / receive fax. It combines a highly efficient design easy installation and high performance in a surprisingly low-cost product. With its small size light weight and integrated USB cable this USB modem is perfect for travel home or office use. Chipset: Conexant; Interface: USB; Transmission rate: 56K; Data protocol: ITU-V.92 V.90 V.34 V.32bis V.32 V.22bis V.22 V.23 V.21 Bell212A 103; Data error correction: V.42 MNP2-4; Data compression: V.44 V.42 bis MNP 5; Command system: EIA / TIA578 Class1 compatible with HaysAT command set; Flow control: Software (XON / XOFF) or Hardware (RTS / CTS); Dial mode: Audio pulse; Quick lightning protection circuit; System requirements: Celeron300 or PentiumMMX266 above; Driver supports Windows 98 98SE ME 2000 XP Vista 7; Cable length: 14cm