The cable on the solar NPS100 panel is very short which makes it difficult to charge your power station and run a fridge in the truck at the same time. I needed some extra length but did not want to get a 10M extension. I purchased the 5M parallel cable (I currently use with one panel only) and it works great. I don't have to carry the extra 5M of cable and if ever I purchase another panel, I won't need to spend more money buying another cable. Great quality cable, I've tested it a couple times with the extension and without and the wattage drop in between 4-5%, which is not bad for adding an extra 5M of cabling.