TCS 1366 MC-1″ Harness with 8-Pin NMRA Plug Keith 6 years ago Train Control Systems 1366 MC-1″ Harness with 8-Pin NMRA Plug TCS-1366 The MC-1″ is a 1″ (25 mm) harness with a 8 pin NMRA plug for the MC series of decoders.