It is stranded copper wire. CAT5 Ethernet cable. It is about 500mm long. It plugs into a socket soldered onto a arduino prototype board, which then leads to digital pin 9 and analog pin 0. The setup works fine, with the cable ties as in the picture, but it becomes erratic if they are removed.
The servo is a HITEC HS-300. Im not sure how much current it draws. It is out of an old model aeroplane I had. Im using a 9 volt 800mA power supply. Either with the 9V or the USB cable I get the same problem.