Ive fitted 501 indicators for morettes, to be honest I think ive been an idiot. The extra two wires is just to make wiring easier, it comes with 4 clips to your stock wires clip on to 2 at one end then the two at the other end go to the bulb, not sure why ive been so stupid to be honest. I think its because all of them seemed to have one wire at each end, 4 wires saves you splicing....of course lol. Not sure why both wires are red though, should be one black one red. as resistors work both ways , no polarity