A protein complex that in Methanobacterium thermoautotrophicum is composed of six subunits, and in Methanosarcina barkeri contains is composed of either two subunits or nine subunits. Catalyzes the conversion of coenzyme B, coenzyme M, and methanophenazine to form N-{7-[(2-sulfoethyl)dithio]heptanoyl}-3-O-phospho-L-threonine and dihydromethanophenazine. [ http://www.ncbi.nlm.nih.gov/pubmed/8174566 http://www.ncbi.nlm.nih.gov/pubmed/9063468 GOC:mengo_curators http://www.ncbi.nlm.nih.gov/pubmed/8119281 ]