These are external rack-mountable units typically featuring a mix of SDI, HDMI, component, composite, and AES/EBU audio connections. If you own a modern Teranex converter, you do not need this utility.
The Blackmagic MultiBridge Utility was the only interface capable of unlocking these features. Without it, the hardware was effectively dormant. It provided the necessary drivers to tell the computer (whether Mac or Windows) how to recognize the complex array of inputs and outputs available on the card's breakout cable. blackmagic multibridge utility