• An old extension cord for a phone cable that had both male and female ends to it (an RJ14 to be exact). However, any connector (USB, etc) would have done, as long as it has four wires and you have male and female ends.
• To enable use of the robot when not connected to the arduino, I also cannibalized an extra male connector that I could short out. This will be used to make a "stub plug."
• Two header pin pairs, each 1 x 2 pins. While you can use straight wire instead, these hook up more easily into the protype board (above).
• Some sort of insulation for the cut wires. While electrical tape or shrink wrap could be used, I recommend "liquid insulation," a rubber paint you can find in the electrical section of most hardware stores.