There are five different lengths of DigiLink cables:- The 18" (0.46m) cable is included with eachHD I/O, designed for daisy-chaining multipleHD audio interfaces.- The 12'(3.6m) cable included with each HDCore, designed for connecting the Core cardto an HD I/O.-25'(7.62m) cable is the same length as ProControl and Control|24 breakout cables.-50'(15.25m) cable (sold separately). This is the maximum length supported for 192 kHzsessions.- 100'(30.5m) maximum cable length (sold separately), that only supports sample rates of 96 kHz or lower.