External Fax Modem V.32 bis/V.42bisEasy to use:The economical highly reliable all in one fax modem. throughput up to 57,600 bps using v.42bis data compression standards. Plus you get unsurpassed at&t reliability in this features-packed value-priced fax modem.fax software and toll-free technical support. Dos/ Windows compatibleGreat value: Easy to use. Saves time and money on phone line costs.