Product Code: VOP-PHO-621004 Description: USB 2.0 Interface, USB 1.1 compliant Built in 16 bit sound card Supports H.323, SIP, MGCP etc Supports product serial write-in With HID (Human Interface Device) Feature Supports Real-Time verification With PID (Physical Interface Device) Feature LED indication of Power and Linking Status Adjustable volume for handset Supports E.164 dialing rule Supports recording feature Self powered via the USB port Compatible with Major Internet Phone Application Software Supports Win98 SE/Win ME/Win 2000/Win XP/Mac OS/Mac OS X Support Skype, MSN, net2phone, etalk, Stanaphone, SJphone, X-Lite, X-PRO, Firefly, Eyebeam, etc. Specification: L. W. H:88*37*20 mm 240 g ( 1 pcs ) Weight:33.5X56X22 cm 9.6 kg ( 40pcs )