Hello to all & thanks again for your help in the past,

I have a trailer question. I just ordered the Show Chrome trailer hitch and wiring harness. According to what I have read, this harness terminates with 5 bare wires. I guess they expect you to wire on whatever plug you want. I have read that the Can Am OEM trailer uses a 4 wire system. I'm wondering why Show chrome would use a 5 wire system when the the OEM trailer uses 4 wires?
The trailer I have has a flat 4 wire. I need to put a round 5 pin plug on both the trailer and Spyder(that's just what my friends have and I want to be able to pull their trailers as well). I am assuming 1 wire for running lights, 1 for brakes, 1 for turn signals, and a ground. That makes 4 wires.? Is the 5th wire suppose to be hazards? Anyway, back to my original question as to why 5 wires when BRP uses a 4 wire system?? Thanks-----Dan