Function characteristic: 1.Free call charge from PC to PC through internet, and call from PC to PSTN at very low price 2.USB port plug and play instant 3.Break through any private networks and firewalls and connect quickly 4.Provide clear and smooth voice without delay or echo 5.Convenient for receiving and hearing with indicating ring 6.It's especially use for SKYPE, and support other network software of MSN, Net2phone,ICQ, OICQ and so on. System requirement: 1. Any computer with USB port 2. Operation System Support: Microsoft Win98SE, WinME, Win2000, and WinXP. Unit price: USD8.5 (FOB Shenzhen) Minimum order quantity: 1000units Payment term: T/T 30%,70% Delivery leadtime: 20~30 days Quality certificate: CE Please feel free to contact me if any question. Sales manager:Denise Ling(Denise#sinovoice.net)