Buffalo Portable Drive USB 2.0. DVD-R write speed: 8 x, DVD+R write speed: 8 x, DVD-RW write speed: 6 x. DVD+R read speed: 8 x, DVD-R read speed: 8 x, DVD-RW read speed: 6 x. BD-ROM transfer rate (sustained mode): 480 MB/s. Interface: USB 2.0. Compatible operating systems: Microsoft Windows 7, Vista, XP SP2