Battery Power 
product Power Media Battery Power /product/m-3-pin-to-f-3-pin-xlr-power-extension-cable-5m-length/ $22 Power Media 
Power Media · Battery Power
(M) 3 Pin to (F) 3 Pin XLR Power Extension Cable 5m Length
You might also need
Battery Power 
10A 4 way IP66 RCD Power Board w/ 1.8m braided lead
Battery Power 
10amp / 10m Extension Lead 1.5mm Rubber Flex Cable (Green Tag)
Battery Power 
10amp / 10m Extension Lead Piggyback (Blue Tag)
Battery Power 
10amp / 15m Extension Lead 1.5mm Rubber Flex Cable IP66
Battery Power 