Black Box Products Video & Multimedia > Baluns click photo to enlarge Balun Module G.703 modules to convert 75-ohm dual coax hardware to 120-ohm, twisted pair. MT243C-F Extended Double DiamondTM Warranty Available (3 Additional Year) Product Highlights Use with our Balun Chassis to build a Balun Mate with only as many conversions as you need. Matches the signal impedance and the pulse shape of the signals according to the ITU G.703 standards.