We have hand warmers on a couple of the Kawasaki sleds. None of them interfere with the lighting. Double check with the manual about how many watts the sled puts out then deduct for your head light, tail light and instrument lights that will tell you how much wattage is left over for the hand warmers. Like Mark says, all of ours connect to the lighting circuit, and I think, although am not entirely sure, that there may be an extra plug on the Kawasaki harness for just such an installation. Some of our warmers are dual temp and have a resistor connected to a three position (on-off-on) switch. At 30 degrees they can be too hot, but under 15 it can be a nice addition.