Forms a nucleosome-like histone octamer containing two molecules each of H2A, H2B, cid and H4 assembled in one cid-H4 heterotetramer and two H2A-H2B heterodimers. The cid-H4 heterotetramer is more compact and structurally more rigid than corresponding H3-H4 heterotetramers (By similarity). Interacts with the condensin subunit Cap-G.