Class NUMBER@1 units have dual-power pick-up , from either NUMBER@2 kV alternating current -LRB- AC -RRB- overhead lines for services north of LOCATION@1 , or NUMBER@3 V direct current -LRB- DC -RRB- third rail to the south .

Class NUMBER@1 units have dual power pick-up , from either NUMBER@2 kV alternating current -LRB- AC -RRB- overhead lines for services north of LOCATION@1 , or NUMBER@3 V direct current -LRB- DC -RRB- third rail to the south .
