Linksys Dual-Mode Internet Telephony Kit. Interface: USB 1.1. Bundled software: Skype. Weight: 130 g, Dimensions (WxDxH): 47.37 x 132 x 34.62 mm. Compatible operating systems: Windows XP / 2000, Minimum system requirements: CD-ROM, Minimum RAM: 128 MB. Operating temperature range (T-T): 0 - 46 °C, Storage temperature range (T-T): -20 - 76 °C, Operating relative humidity range: 10 - 50 %