The pairs on MMHR and Speakerlink are wired exactly the same as cat5e/6/7 ethernet. Otherwise you couldn't just take any straight cat5e/6/7 ethernet cable and expect it to transmit Speakerlink or MMHR.

The physical 100 ohm layer is the same. That is why you can use any conforming cable in your household.

DSP8000SE, DSP7200SEHC, DSP5200SE sides, DSP7200SE rears, 861v8, 210, Sim2 Ultranero 4, Stewart Cinecurve 2.35:1, XEIT CM-5E Anamorphic lens, Dune HD Duo Cinema 8K and Wireworld Platinum 48G HDMI -> UHD722 -> Shunyata Omega Ethernet. Shunyata/Furutech power-cables/filters. SR Master Fuse@861v8. Uptone Etherregen with 10MHz OCXO clock.