Skype usb phone 1.rational structure, beautiful appearance. 2.independently developed 3.reliable quality 1. PC-to-PC and PC-to-phone operation; ... No external power required; 5. Complies with H.323, MGCP, SIP protocol; 6. Echo cancellation, noise reduction; 7. Support Skype, ... UUcall, Alt, QQ, MSN, Talk, Yahoo, Sip Discount, X-Lite, Eyebeam, X-pro, Sipgate, IPhone, Vonage, UBIFONE ...