Zoom 2949. Modem speed: 56 Kbit/s, Interface: RS-232. Supported data transfer rates: 56 /33.6 kbps, Maximum fax transfer rate: 14.4Kbps. Minimum system requirements: PC w/ RS-232, Minimum RAM: 16 MB. Power supply type: 120 VAC, 60 Hz. Dimensions (WxDxH): 133 x 38 x 165 mm