The Mark V Speedtronic DS200TCEBG1A is a Common circuit EOS card which is known as Protective Termination Expander Board.The DS200TCEBG1A has four signal transformers,three bayonet connectors,one 26 pin connector,four 10 pin connectors and three 20 pin connectors.The DS200TCEBG1A holds the alarm horn for Mark V LM, The board has an audible alarm.The Mark V DS200TCEBG1A is located in location 2 of core.Always adhere to the manufactures installation guidelines while installing or replacing the board.