The Blackmagic Design Universal Videohub SDI Interface includes 4 SDI inputs and 4 SDI outputs, plus 4 deck control. In addition, it comes with full re-clocking and auto switching SD, HD, and 3 Gb/s SDI (serial digital interface). The SDI interface connects all devices in a facility by covering long distances up to 300' (91.4m). It uses 10-bit video quantizing that allows 1024 video levels, and eliminates banding and contouring problems in high quality video.
For further information check out the Blackmagic Design website