True about Intercalated Disc is :-

The Cardiac Muscle develops by joining the cells end to end through anchoring cell junctions called the Intercalated Discs that form the distinguishing feature of Cardiac Muscles. These Dark Staining discs found at irregular intervals and represent the specialized junctional complexes between the cardiac muscles. They appear as Straight bands or Staggered across individual fibers. Inter-digitating intercalated discs are composed of Fascia adherens, Desmosomes, and Gap Junctions.