... power(W)Battery/CapacityLampDischarge timeES-EM16WH16W3.6V 2.5Ah Ni-cdPL,PLC,D/E,T/E>2 HourES-EM16WK16W3.6V 4.0Ah Ni-cdPL ... ,PLC,D/E,T/E>3 HourES-EM28WH28W3.6V 3 ... .0Ah Ni-cdPL,PLC,D/E,T/E>2 HourES-EM28WK28W4.8V 5 ... .0Ah Ni-cdPL,PLC,D/E,T/E>3 Hour 16W/28W ...