This is the cable which plugs into the wall and goes to the tranformer It is not the part that plugs into the laptop and has the box (transformer). (half of Dell part # U7809) I bought a second A/C power unit from Dell and only needed the second part of the package. If you are buying an OEM/aftermarket replacement, you might find the cord to be only 4 or 5 feet long. This is original length, 6 feet! Dell 6ft Power Cord 110 D3W/3P Mfr P/N 06U340