I put a set of oxford heated grips on my america and chose to use the battery as the power source which allowed me to use the fuse supplied, however to stop the risk of accidently leaving them on and flattening the battery I installed a relay switch which fitted nicely under the seat, the relay switch is powered of the tail light. I joined into the tail light under the back fender. This way if i'm going to blow a fuse it is only the tail light, relay switches take very little power, this set has worked fine for me for quite a while... good luck
