original spots are spliced into the H4 connectors, so you dont HAVE to relay them they'll still work even if main headlight plugs are completly disconnected. thing is the spots are still pretty damn bright even if not relayed, obv be brighter if you do. comes down to how often you use your main beams, relaying the dipped beams is prob gonna see the most benefid day to day, unless you live out in the countryside and do a lot of night driving.