The group's principal activities are to develop, manufacture and market proton exchange membrane fuel cells, fuel cell engines, sub-systems, electric drives and power electronic products. the group operates in three business segments: fuel cells, fuel cell and other systems and carbon products. the fuel cells segment develops, manufactures and markets proton exchange membrane fuel cells. the fuel cell and other systems segment provides power for transportation engines and stationary power plants. the carbon products segment develops, manufactures and markets carbon materials for automotive and fuel cell applications. the group operates in the united states, japan, germany and other countries. fuel cells accounted for 62% of 2001 revenues; Carbon products, 22% and fuel cell and other systems, 16%.